A National Migraine Centre Heads Up Podcast transcript
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Transcript
00:00:00
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00:00:35 Dr Katy Munro
Welcome everybody to this episode of Heads Up podcast and today I’m delighted to be talking to Doctor Nick Silver about cluster headache. Doctor Silver is a consultant neurologist with a high interest in headaches and of every different type. He works at the Walton Centre in Liverpool, and he’s also a trustee of OUCH and The Brain Charity. So thank you very much, Nick, for coming on the podcast. And although we have done one episode on cluster headache already, I felt it was quite useful to do it again, because there have been some developments which we can touch on. And also I know that you have a special interest in this subject, so it’s brilliant to have you on as a guest. Can you just tell us a little bit about yourself?
00:01:23 Dr Nick Silver
OK, thanks ever so much, Katy. So I’m a neurologist, as you said, I’m at the Walton Centre. I’ve been there for about twenty years now and started the Northwest Headache Clinic for refractory headache disorders, which has become possibly one of the largest headache clinics now in the UK, we’ve got four consultant neurologists there.
Before I actually was at the Walton Centre, I’ve done my training in London and I’ve been at Queen Square, the Institute of Neurology, and originally I did a PhD in MS and while I was doing that and even before that, I was always very interested in symptom control. And over the time of my PhD I started working with Peter Goadsby and I started noting that a lot of patients that I saw with certain symptoms would often turn out to have them associated with headache disorder. And I suppose in the first instance I got really interested in things other than headache within the context of headache disorders. So all the non-headache symptoms and how things fit together.
Now I was very interested to– I mean when I was training, I was at the Queen Square and there were so many consultant neurologists that we would be working for and all had a completely different way of managing headache. And I wanted to know what the right way was and it was clear that there were emerging trends towards the right way in headache. But everything was so variable, what we believed in, what we understood, just so variable and I got really interested in that and really felt it’s so common, it’s so disabling, I really need to get on top of this. And before I knew it, I’d jumped ship from MS, become a bona fide headache sub-specialist neurologist and was really most interested in headache disorders. And I suppose my overall path you mentioned: I’m interested in cluster headache, I’m clearly very interested in cluster headache. I’m interested in the other headache disorders that that look like cluster headache. Particularly things like hemicrania continua. And I suppose I’m really interested in the non-headache manifestations of other headache disorders. How things present. Either with headache or without headache or with little headache, but maybe cause a lot of disability through other means, such as fatigue or cognitive disturbances, or sleep disorder, etcetera. So yeah, that’s my journey.
00:03:44 Dr Katy Munro
Excellent. So one of the reasons I asked you to be a guest is that I heard you give a talk to the OUCH conference back in the summer and what really struck me was your introduction to that, which was four different cases with different symptoms, some of them that you would think, oh yes, that could be cluster headache. But they were all so variable and yet they all turned out to be cluster headache. So can you just say a bit about cluster headache and why you think it’s important? And we’re focusing on it, particularly in this podcast, but generally why people should understand it better?
00:04:19 Dr Nick Silver
So cluster headache’s not as uncommon as we think. It’s about one in a thousand people. Certainly historically, it’s been a condition that’s been very poorly recognised and very poorly diagnosed. And a lot of people go for many years before they receive a diagnosis. When I first started in neurology, people would be going maybe eighteen-twenty years before receiving a diagnosis of cluster headache. And it’s all very well if you’re if you’re going to have a, oh, this treatment, treatment X, treats headache. That’s fine. If that does it all that’s fine, but it’s not. Cluster headache has really very different treatment options, different things work for migraine to cluster headache.
People were getting short shrift and it’s interesting to think that the male-female ratio was sort of thought to be 10:1 back in the old days and now it’s probably more like 3 or 4:1 male to female. And I don’t think it’s physically changed. I just think that women used to go to the GP or to their doctors. And everything was just thought to be migraine. And I think women in particular have had short shrift from getting diagnosed with cluster headache and I suspect it’s women’s fault because women have a much, much better pain threshold than men. I mean, they go through childbirth. You know, men just complain that their hand hurt when they were squeezed during childbirth. And women actually go through so much pain that I think women are actually far better at pain than men. That might be a controversial point and that’s just my own thoughts.
But I think that because women are much more hardy sometimes than men, I think that they don’t necessarily complain as much to the doctor, and it doesn’t come out at quite what they’re going through. And it’s interesting when you see people in clinic and they’ll say, well, you know, you’ll ask them, what do you do, what happens all night? I get up and I, you know, I might go to another room when I get my headache. And the husband said, no, tell the doctor. Tell the doctor what you actually do, because actually, when you see someone in a cluster headache, it tells a very different story. And actually just to bring it back to the OUCH UK conference that we both went to, I said at that conference that if they needed me, I’d be there to help with any patients and they had a quiet room set aside and one of the trustees came and said, oh, Nick, can you come and help? We’ve got someone who’s really struggling? And it was a young girl who had come from another country. She was living in the UK,I think she was about twenty years old or so, and she was curled up in the corner of the room absolutely distressed. I mean, she was rocking. She was banging her head. She was just so, so agitated and distressed. And you just felt so helpless watching her, and especially in a scenario like that, thinking, what can we do? We had oxygen there. Someone actually kindly gave me an injector of sumatriptan to give her. And then she gradually settled down. But during that time, you know, if you were a vet rather than a doctor, there’s no doubt what your treatment would be. You know, you wouldn’t let someone carry on suffering that way.
I know I’ve veered away from what you asked originally, but I don’t think that people quite recognise the severity of cluster headache and I suspect that’s why it’s been more recognised in certain people than others and people don’t have their headaches during the time they’re seeing GPs or other people, so they go, oh, it’s a headache, you know. They don’t quite realise what it’s about.
00:07:52 Dr Katy Munro
Yeah. And I know there’s a certain number of people who have cluster headache, who feel that the term cluster headache itself isn’t helpful, but it’s one of those things which is very unlikely to change. But I agree with you. So when you’ve seen somebody in an attack and when we used to have a clinic that people would come to, before the lockdown when we went virtual at the National Migraine Centre, we would occasionally have patients with cluster headache who would come in and have an attack in front of us and we had oxygen there obviously. And it was so impactful to understand how much suffering people with cluster headache go through. That’s why I try and talk about it whenever I’m doing a podcast about anything that vaguely I can talk about cluster headache as well just to make sure that more people understand and because there is this confusion that sometimes people have been told, oh, you’re getting a lot of migraine attacks one after the other, you’ve got cluster migraine, and we’re like, no, no, no, let’s not talk about cluster migraine. That’s very confusing.
00:08:58 Dr Nick Silver
Cluster migraine is like saying that you’ve got a Bentley Mondeo or something. You know, they’re two different cars. They’re probably actually made by the same manufacturer, I don’t know my cars, but, you know, cluster headache and migraine are two completely separate entities. And that they’re really very, very different. So yeah, we know we try not to use those terms.
00:09:21 Dr Katy Munro
I did have a patient the other day who saw me with a bit of hope, actually, because she had had migraine for many years and then she started getting very typical cluster headache, I mean almost textbook cluster headache attacks in December. She went to her GP, who said, I think you’ve got cluster headache and she came to see me the other day and I thought, well, you know that’s progress, you know, to get a diagnosis from your GP, a referral appropriately. We put in a plan and, you know, she now knows the diagnosis. But as you said, it’s just taken a long time.
00:09:59 Dr Nick Silver
It’s a two-way process. We’re seeing more people diagnosed with cluster headache now than we were before by GPs and that’s great. But I’m also seeing a lot more people where they say, oh, we think this might be cluster headache because someone for instance had some eye watering or some nose running or there were certain features about it. And quite commonly we’ll see that where clearly it’s not cluster headache, it’s one of the different conditions, but at least people are recognising things other than other than migraine.
Coming back to what you were just saying about seeing people in attacks. We used to and I still do it occasionally, hardly ever now, and again it’s this thing about going remote and what happened in the pandemic, but I used to bring people in to give them their cluster headache attacks and I would actually give them GTN spray, which is an angina spray, to see if I could trigger it. If I wasn’t sure what the diagnosis was, I’d bring them in, I’d try and trigger one, and then while they’re there, I’ll be able to see the objective features of autonomic disturbance, of restlessness and agitation. And then I would also be able to trial some oxygen or triptan, again to see the response. And I used to find that quite useful in in cases where there’s diagnostic uncertainty.
So I think actually triggering an attack can be useful and coming back to the point that I made before about, well, the GP doesn’t see it. So they’re not necessarily going to know quite how bad it is, you know, to turn around and say, oh, I had a headache last night, doesn’t encapsulate anything to do with what they had. And actually I tell patients, and I probably shouldn’t do this and I probably shouldn’t admit it to a GP. But if someone’s in a bout, I’ll say, well, look, if you’re not getting anywhere, just go and go and sit in the GP practice and just sit in the waiting room and have a little shot of vodka or whiskey or something. And if they ask you why you did that, just say, well, it triggers my headaches. But I’ll tell you as soon as you’ve got one, oh, you’ll be seen straight away, and before you know it, you’ll have your whole supply of triptan injectors.
And I think people who have had a history given to them will often go, oh yes, that sounds nasty, but as soon as someone has seen someone with an attack, that treating clinician will be invested, whether they were invested or not before, they will do everything that they can to help that person, because it’s just such a — I don’t know you, it comes back to the idea of transference. I don’t know what you thought when you saw patients who are in attacks, but I feel despair, helplessness, absolute helplessness. And I think when we see a patient with that, we recognise that transference, what we feel is what they feel to some extent. And I think it really does really get you on track to treating that patient and doing the right thing for them.
00:12:47 Dr Katy Munro
I do sometimes suggest if there is somebody else with them that they get that person to video them during an attack. And so that can be really helpful. And I think OUCH, talking to members about doing some videos and putting it on the OUCH website. You can find them on YouTube if you do a little search. But yeah, I think that’s crucial.
So should we just outline the differences and the similarities between cluster headache and migraine, because there are some overlapping symptoms. You were mentioning the autonomic nervous system and of course the autonomic nervous system is the system that controls the automatic processes like sweating or breathing, pupillary dilatation and things. So that is affected by both cluster headache and migraine, but one of the significant differences is that cluster headache is always on one side. And I’m saying always and you’re going to probably say nearly always. Is that right?
00:13:51 Dr Nick Silver
Yes. You know me well, Katy. So yeah, migraine versus cluster headache. I think this is always quite a difficult one. But what I will often say is that all the symptoms, we think all the symptoms we actually ask patients about headache are fairly useless. You know, the standard symptoms. Like where is the headache, does it cause nausea, does it cause vomiting, is it sensitivity to noise, is it sensitivity to light or smell? Those questions actually are non-differentiating because if you have a predisposition to migraine genes, when you get your headache disorder, whether it’s migraine or hangover, a bang on the head, it doesn’t matter what it is. Cluster headache, brain tumour. When you get your headache, you’re going to potentially have those migraine features because they get recruited so you can feel sensitive to noise or light or smell. So that doesn’t really help us.
I think with cluster headache, there are a few things that really, really help us. For instance, for a majority of patients they’re in episodic cluster headaches, so there will be a time of year where they go through what I would term a bout. And during that bout they will have individual attacks of headache. So that bout typically might last, say, six weeks or four weeks to twelve weeks, say. I’m sure there’s literature to tidy that up in terms of the exact time, but generally somewhere around four to twelve weeks someone will start to have headaches and a bout typically will start off with fairly mild headaches and maybe not even that frequent, they might be one every other day or something, or one a day. And as it builds up, the attacks will become much more severe by, say, a week or two weeks or three weeks. There will then be a sort of plateau where they’re really cruising along at a horrible frequency and severity, and then it will probably start to come back down again. That’s the sort of traditional pathway that someone will have going through a bout.
And that’s different from migraine, where with migraine, what you might see is you might see an attack happen that will last, say anywhere between hours and a day or two, and then they may have another one a few weeks later, a few weeks later, another one a few weeks later. So the time course of these things is very different. That’s the first point.
The second point is that migraine, although it was always talked of as a one-sided headache, most patients that we see with migraine will at times have headaches on either different sides or both sides. So if I see someone where say they’ve been referred and it says, can you see this person who has always had left-sided headaches, that’s a little alarm flag for me to think, well, hold on, could this be a trigeminal autonomic cephalgia? Because the TACs, for short, generally are one-sided. Just to confuse it a bit, cluster headache could happen on the left side this year and next year could come back on the right side. So the bout itself is usually on one side but a different bout may happen on a different side. So it’s not a pathology in the head or something localised to the head which makes it happen in one side. It’s a condition starting in the brain. But because it’s in the brain, it can occur on the other side of the head.
Coming back to your comments as to whether it’s always unilateral, 99% are unilateral and I think if you’ve got someone with a bilateral headache, think again. It’s probably not going to be a cluster headache. And actually if it is sounding very much like cluster headache, I’ll probably image them because they’re atypical. And people with atypical cluster headache or atypical TACs, or someone who’s having their first bout, I would image. If someone’s had five bouts over the last ten years, there’s not really much point in imaging them because they’ve been normal in between the bouts and they’ve been fine. So the chance for pathology taking days or weeks or months off is really quite, quite remote. The next thing about the cluster headache, so we’ve talked about the site in terms of it being one-sided. It’s often around the temple, the eye, the nose.
But it can be anywhere on the side of the head and actually head pain disorders don’t just cause pain in the head, they can cause pain in the neck, in the arm, in the leg. We don’t often see that with cluster headache. But just beware that it might not be completely limited to the head. It’s usually anterior, but it can be posterior. And then the site, as I said, is going to be unilateral in most, but the next thing is the behaviour and I think one of the people I taught when I was doing a national mentoring course, one of the Italian doctors there, came out with this term, the wounded lion versus the wounded lamb. And I think that’s quite a nice description between migraine and cluster headache. In migraine, you go and lie down in the dark. You take yourself away and you say, woe is me and you put something on your forehead and you stay very still. Movement makes it worse. Now in cluster headache, movement can still make it worse, but you just can’t stay still. You’re restless and agitated. I suppose the equivalent to that, if you imagine that you kicked, you know, you’re wearing your flip flops and you kick a rock. You don’t just stand there and go, oh, oh my, let me keep my foot still. You jump up and down and you know you can’t stay still very easily. And I think you know, in cluster headache the pain is going to be far worse than stubbing your toe. But it’s got a restlessness and agitation to it that’s inherently biological.
If we look at people having awake brain surgery where they’re having a probe, a little wire put into their brain, say for movement disorder surgery and you start stimulating the area just behind the hypothalamus, where we know on function imaging that’s pretty much where the cluster headache seems to originate from in an attack. If we stimulate that specific area then you’ll start to see restlessness and agitation in that patient. So the restlessness and agitation is a biological feature. It’s not, this is bad, I’m therefore restless. It is a biological feature. So we’ve talked about the site, talked about the restlessness and agitation.
00:19:50 Dr Katy Munro
Hi, can I pop in then?
00:19:53 Dr Nick Silver
Yeah, of course.
00:20:04 Dr Katy Munro
So I was just going to say, if you say restlessness, it sounds like somebody’s sort of just moving slightly in their seat, maybe a bit of fidgety, but I had a lady the other day. And she said, when I have a cluster headache attack: the first one I had I pounded my head with my fist so much that I had a bruise on my head, and she had friends come round to help her, to call an ambulance for her because they didn’t know what was going on, and she said they were so shocked to see how I was behaving, you know, she was hitting her head on the wall and things. So it’s extreme, isn’t it?
00:20:28 Dr Nick Silver
It is extreme. Yeah, it’s extreme restlessness and agitation. So you see and hear of horrible stories with this as well. I used to put a slide up of a an X-ray of the skull which just had shotgun pellets all around one side of the head. And this guy wasn’t trying to kill himself. He was just trying to take the front of his head off and the eye out where the pain was originating from. And it’s not unusual for people to say, look, if I had a knife or something, I’d be tempted to take my eye out. We see people who extract their teeth in these attacks. We see all sorts of behaviours which are just trying to get rid of the area of pain. Unfortunately it doesn’t work because the pain isn’t actually in those areas, the pain is experienced in the brain.
I mean, it’s quite difficult trying to explain that pain is experienced in the brain to patients sometimes, but if we think about a man who’s lying on a battlefield, having lost his arm. He may not actually be aware of pain for that first half an hour until he’s off the battlefield, and then he’s in severe pain. And actually go back to him four months later and he’s got pain in his hand even though his hand’s no longer there. So he’s got phantom limb. So pain you can turn right down or right up with various different behavioural pathways or mechanisms, but the whole point of that is that the pain is experienced in the brain, so taking part of your eye off or doing something isn’t going to help, but patients just feel absolutely compelled to tie something very tight around their head or push in.
You know, it’s no good saying, do you go to bed with a headache? That’s no good. Because if you watch someone with cluster headache in bed, they’re usually on all fours, their head’s pushed down into the headboard or the pillow. They’re agitated. They’re moaning. They’re screaming. You know, it’s obviously a different behaviour to someone who’s lying still with a migraine and who just can’t move. It doesn’t mean that movement doesn’t make it worse. Some people with cluster headache are between the devil and the deep blue sea. They’re moving around, it makes the headache feel worse, but they can’t help moving.
00:22:46 Dr Katy Munro
I suppose it’s in the timing, isn’t it? Because I’ve read comments from people saying, you know, I put off going to bed because I know if I go to bed that an hour and a half later I’m going to get an attack, so I try and not go to bed. And there not just a seasonal thing about it, but there’s a sort of circadian rhythm, isn’t there, throughout the day sometimes.
00:23:07 Dr Nick Silver
Yeah. So that’s exactly right. So the alarm clock headache. Being woken from sleep is a real marker that you need to–. If someone’s woke, I mean, there was a really good paper just at one of the recent international headache meetings looking at the timing of onset of migraine and actually the commonest onset of migraine was from sleep, which this whole idea of referring everyone up on a two-week pathway when they wake up from sleep thinking they’ve got something nasty going on. I mean, migraine wakes you from sleep, but it wakes you most commonly between sort of six and eight in the morning. Cluster headache tends to, as you say, wake you an hour, an hour and a half after you go to sleep at night and it’s commonest at night. Now, that doesn’t mean that everyone has nighttime headaches. Some people have daytime headaches.
Some people are able to carry on working because they just get their headaches at night and their daytimes are reliably headache-free and some people get a mixture. But the nighttime is by far the commonest and people often find that they’ll have one attack and then there might be another or another so, you know you can get up to six to eight attacks. Excuse my dog in the background. You can get up to six to eight attacks per day. And occasionally we see people with even more attacks. Although then we start to question whether it might be a different headache disorder.
Site behaviour. The actual timing of attacks, and again coming back to that area behind the hypothalamus, that’s where we think the clock is in the brain. And so we think that relates to the seasonal variation, the fact that these are most commonly seen bouts in spring or autumn, we get people who go on long distance, long-haul flights and they’ll get a cluster headache when they swap through the time zones.
And then we’ll get patients who as you say will have a very typical timing during their attacks and it will have this circadian rhythm to it. So those are features. Coming back to things that are migrainous, sensitivity to noise and light. Sensitivity to light’s often in just the one eye. That’s a bit of a clue. It’s not a strong marker. Sensitivity to noise is there. I think we see very little in the way of sensitivity to smell, osmophobia, in cluster headache and conditions like hemicrania continua, which are possibly more related to cluster headache than migraine. I think it’s extraordinarily rare to see increased sensitivity to smell, when I’ve asked patients, so these are little sort of nuances of attacks that give you slight clues.
I mean, you will have some patients with nausea or vomiting or stimulus sensitivity, but I think that the level of the pain is of such a magnitude that I think that people aren’t really aware of the sensitivity to noise or light or smell or other features because they become nothing in comparison to the level of pain.
00:25:56 Dr Katy Munro
The eye watering and eyelid drooping and nasal stuffiness is quite a feature, isn’t it? You can get quite a red eye High but that of course can also be a feature of migraine, so that again, not really such a distinguishing thing, but also very common in cluster headache.
00:26:05 Dr Nick Silver
Well, I think it’s almost always seen in cluster headache. In fact, I’ve seen patients who only have the autonomic disturbance, they get the typical timing of attacks of autonomic disturbance with no pain. They may even be diagnosed with a partial Horner syndrome with a small pupil and that can be seen in between attacks, a small pupil or a droopy eye that you can get as a pervasive feature, and I’ve seen that occur in the patient a number of years before they developed the headache. So these things are not necessarily all tied in with the headache. But yeah, the autonomic disturbance in cluster headache I think is useful because if it’s not there, you question the diagnosis. It’s usually fairly extreme when it’s there. Migraine can cause autonomic disturbance, it’s mild, a bit of a red or watery eye, or droopy eye.
With cluster headache i’s often really, really objective. People can see it. Marked redness, running, drooping of the eye, twitching of the eye I think is linked in with that, stuffiness and running of the nose, flushing, sweating, oral fullness, fullness in the ear and tinnitus. So those are the main cranial autonomic features that we see with cluster headache. And of course there are more systemic autonomic disturbances that we see with all headache disorders, so increased passing of urine or diarrhoea. You sometimes see flushing in the limbs and other things, and swelling of the limbs I’ve seen. So you can see more obscure symptoms. But the big difference between cluster and migraine is that the autonomic disturbance is usually marked.
00:27:51 Dr Katy Munro
So just say a bit if you would about episodic and chronic cluster headache. So episodic is where you have a bout and then it goes away and that can be for quite a variable amount of time, can’t it? Sometimes people are saying, well, I’ve had it in March, I’ve had it in September, but some other people say, well, I haven’t had it for five years and now it’s back again. What? Any thoughts on that? I mean, that seems such a strange thing, isn’t it?
00:28:23 Dr Nick Silver
It is, but I think again that links into the area behind the hypothalamus. It’s near the biological clock system in the brain.
The episodic is far more common than chronic cluster headache, although as treating neurologists who specialise in cluster headache, we tend to see a lot of chronic cluster headache. But I think we’re seeing a biased sort of presentation there because we see more people who are struggling to be managed. So we see more of the chronics, but if we look at epidemiological studies, it’s far more common to have episodic than to have chronic. You can go either from episodic to chronic or vice versa, but most people start off episodic. A small proportion of those become chronic, and it’s very rare to start chronic, and it’s even rarer to start chronic and go back to episodic. So that sort of puts the chronic and episodic variations in time.
For people who are getting episodic cluster headache, they shouldn’t worry that they’re going to become chronic because you know the majority of people don’t become chronic. So I think there’s some reassurance there for that group of patients. And then of course we’re seeing this. Interestingly, I think there’s a slight sex difference as well in those. So the chronic cluster headache patients tend to be very much more male than female. That’s from the limited data we’ve got so far, and the episodic cluster headaches tend to be about 4 or 5:1 male to female. Well, so yeah, it’s closer male to female for the episodics.
00:30:08 Dr Katy Munro
That’s really interesting. So do we know anything about the sort of triggering factors? For example, do we think it’s genetic? And also we know that cluster headache in bout people are triggered by alcohol. We know that smokers are more likely to develop cluster headaches. But sadly, giving up smoking doesn’t necessarily make the cluster headache go away, but also the overlap with migraine and what you’ve just said about women. Is there any influence of hormones? I mean, that’s about four questions for you to answer next.
00:30:41 Dr Nick Silver
Yeah. So where do I start on that? Starting with the hormones and I don’t think we do see generally an influence with hormones. I think some people with their cluster headache may find it’s a bit worse at certain parts of their cycle, but it’s not really a big feature. And I think the hormonal side is nothing like that we see with migraine, I think it’s pretty independent of hormones. Maybe that’s why we see it more in men than women, you know, it’s got the opposite way around from migraines in that perspective where women with migraine are far more likely to be noted with it. And that’s probably because of their hormonal triggering.
Smoking is really interesting and I think really unknown. At least I don’t know the answer to this. Unfortunately, stopping smoking, as you say, doesn’t do anything. It doesn’t change your potential to get cluster headaches. It just means that you’re more likely to live longer, and that’s quite a good thing really. So smoking, we don’t understand why.
I don’t think my mum would mind me mentioning her. She was one of Peter Goadsby’s oldest patients at presentation. I think she presented when she was about eighty. She’s still going. She’s ninety-six and she’s still smoking. And gets her cluster bouts about every seven years, absolutely the same each time. So yeah, that’s a bit of a an unusual one, but for most people, I would recommend they stop smoking. It’s not going to make a difference to their cluster headache, but it’s generally a good idea. And then so we talked about smoking. We talked about women.
Genetics. There have been some studies looking at the whole genome which we’ve participated in as well and they’ve been interesting in that they’ve shown certain areas that look interesting, but it’s not the sort of thing that you pass down as a gene to your child. You know, some patients are really worried that they’re going to have a child who suffers from what they’ve had. And that’s not what we see. There’s a very slight increased risk within families, but it’s minimal. Whereas with migraine, most patients that we see with migraine will report a family history.
There was a fourth question in there and I don’t think it was to do with failing memory.
00:32:57 Dr Katy Munro
Alcohol.
00:33:06 Dr Nick Silver
Not yet, it’s too early. Yeah, so alcohol is interesting in that it triggers the attacks when you’re in a cluster bout, but it doesn’t when you’re not in a cluster bout and the same with GTN, it triggers in bout and doesn’t trigger out. So there’s clearly two different states of the brain to be in between the attack and not in between, in the bout and out of bout and it’s a switch that changes the way the brain is responding to external factors. So.I use that quite regularly in clinical practice. Alcohol, as I mentioned already for people to be aware of what an attack looks like to trigger one. But also I think when people come out of bout and they’re say they’re taking verapamil medication. A useful thing to do if alcohol triggers their bout is if they’re not sure whether they’re coming out of a bout because they’re on medication or not. Firstly, are they getting any shadows? If they’re getting shadow attacks where it just feels like it’s going to happen and doesn’t materialise, then they’re still in power. The drug’s working well. That’s an optimal situation because you still know that you need the drug. But if they lose their shadows, they don’t have shadows, it’s quite useful for them to have a drink of alcohol and see whether that actually triggers an attack. Because if it doesn’t they’re out of bout and they can just get on with things and reduce their medications very quickly.
People don’t need to be on medications in between their bouts for the vast majority, most people can come off their medications and say it’s something like verapamil, you can get back on it so quickly. Within a week you can be back up, or even less. You can be back up to the same dose that you took previously, at a safe tolerated level. We might come back to that later, I suspect.
00:34:40 Dr Katy Munro
We’ll talk about the treatments and just to clarify, the GTN that you mentioned is glyceryl trinitrate, isn’t it, which is a spray that we use for people suffering from angina, so if you are a patient who had angina and cluster headache and you were in bout, you might have to be a bit careful or talk to your GP or consultant neurologist about how else you manage rather than give yourself an attack by treating your angina. I haven’t come across that, I have to say, but they’re out there.
00:35:09 Dr Nick Silver
Yeah, it is difficult because we haven’t really got other options from GTNs to treating angina. I think people with angina get worried that if they don’t treat it and it’s used for it, a lot of people with angina and heart disease get really worried about chest pain, thinking this might be a heart attack that’s going to happen.
And actually when you give them good education, that’s an angina attack isn’t a heart attack and it’s different. And it’s not that you need the angina to prevent a heart attack, it’s just you’re trying to relieve the symptoms, then they can often live with that a lot better.
But it’s a really tricky situation when you have someone. And of course these guys with cluster headache, a lot of them will have smoked. So there’s quite a high risk of ischemic heart disease, they do become more troublesome to treat, and then because they’re smokers, people don’t want to give them oxygen, although we can with, you know, as long as you’ve got certain robust mechanisms in place to ensure they don’t blow up their neighbourhood. But there are some challenges that come along by virtue of this group of patients often smoking.
00:36:15 Dr Katy Munro
So you mentioned a little bit about the diagnosis which is history, history, history and that scans are not particularly useful for this. There isn’t really a diagnostic test for cluster headaches. There’s no blood tests or anything like that that we send people off for. But I have to say from the National Migraine Centre, if we have a patient who has a history that we think is very likely to be cluster headache, we do urge them to get referred for a secondary care, neurology, headache specialist opinion to be under the NHS care because I do think you do need a specialist who understands about treating cluster headache to see these patients. Do you agree?
00:37:00 Dr Nick Silver
Yeah, I do. My only slight worry is that that you may at the National Migraine Centre have more knowledge and I’m sure you do have more knowledge than many consultant neurologists when it comes to treating headaches disorders and you have to bear in mind that you know, it’s a bit like GPs and primary care physicians. You’re a master of many, many different specialisms and you’re having to treat a huge range of conditions and it doesn’t mean that a GP is less intelligent than a specialist. It’s completely not that. It’s just that in fact the specialist would struggle if they only had eight minutes and had to deal with so many conditions. You get a different skillset and a different level of knowledge and actually GP knowledge on so many things is really at a very good level, but it’s just not quite at the top level for certain nuanced issues related to treatment. So I think yes it is, it is a good idea to be under a specialist, ideally a specialist headache doctor rather than a standard neurologist if possible, but obviously that’s not possible everywhere and of course there are many general consultant neurologists who are excellent at managing headache disorders, but you want someone who knows what they’re doing. You want someone who can tell whether you do need a scan or not, and a scan doesn’t diagnose it. It just excludes other things.
00:38:09 Dr Katy Munro
Yeah.
00:38:19 Dr Nick Silver
But as I mentioned before, if you’ve got someone who’s already had three bouts of cluster headache over the last, say, six years or three years and they’ve been fine in between. You know that this isn’t going to be a structural worrying pathology. Quid pro quo, the other side of the coin is that if we scan a hundred people on the street, we’re going to find within that group, maybe two or three meningiomas, we’re going to find some arachnoid cysts. We’re going to find one or two pituitary adenomas. There are all sorts of things that we see in normal people that they will have and take to their grave with no consequence whatsoever when they’re at a nice ripe old age as they should do.
And the problem with scans is that when you’ve got a nasty condition, it does generate a lot of concern, anxiety and worry. So if you find what’s termed an arachnoid cyst, it gets people really worried. It’s not actually a cyst, it’s just a space which the brain didn’t develop in when you were year dot. So you know, for almost all arachnoid cysts they’re incidental. For most calcified little meningiomas, well, we don’t need to do anything with those because they’re calcified, they’ve been there for a long time, they’re not going to change significantly. They’re not causing the headache syndrome.
The difficulties with pituitary and there’s a story that there may be an increased risk of things like cluster headache with pituitary adenomas, small benign lesions of the pituitary gland not causing any mass effect, not causing any pressure on things in the majority of cases. Some of them are big, but the majority are little microadenomas. And are these related or not, I still think the jury is out. I spent a good fifteen years scanning everyone with cluster headache and it never changed my management on anyone. You know, I think it’s something which, unless there are atypical features. Or you know, it’s fair enough to do a scan in the first bout or there are atypical features, but is scanning worthwhile outside of that, I’m not sure, and you may just cause more concern and worry.
00:40:22 Dr Katy Munro
It’s very similar to migraine, isn’t it, really, you know, and also with both migraine and cluster headache, if you’re getting periods of exacerbation followed by a period where for no apparent reason everything calms down again, and if you’re cascading into having an intervention, it’s tricky to know whether that bout would have stopped anyway.
00:40:49 Dr Nick Silver
Exactly. And I mean with imaging in all those conditions I mentioned before, that nasty things don’t take days off. You know, your brain tumour doesn’t have a week or two off. So once you’ve got normal days, it makes it much less likely you’re going to be dealing with something worrying from that point of view.
00:40:59 Dr Katy Munro
Yeah. I just wanted to talk a bit before we come on to treatments about the impact of this on people’s lives and particularly, you know, it can affect their livelihoods, can’t it? So if you’re somebody who suffers from cluster headache but your employer doesn’t really understand it and you’re suddenly having to take six or eight or even twelve weeks off because you’ve got agonising pain. We get a lot of questions about, you know, people who may have lost their job or will be under threat of losing their job, maybe wanting to claim PIP benefit?
00:41:46 Dr Nick Silver
OK. Yeah. OK.
00:41:49 Dr Katy Munro
Any comments about that?
00:41:51 Dr Nick Silver
Yeah, so we know from the World Health Organisation data: they looked at all common medical conditions known to mankind and womankind, and they came out with migraine being the most disabling in women between the age of sixteen and fifty, or roughly those ages. And the third overall, the third most disabling disorder known to mankind. Now when we sit in a headache clinic and we see patients with bad migraine, we recognise that. But if we’ve got patients with migraine or cluster headache, our patients with cluster headache will be in a category way above that in terms of the impact, not only to the patient but the family.
Part of that impact is loss of function. You’re losing sleep not just through attacks, but the sleep quality during a cluster bout is really poor, so you’ve got a group of people who are sleep-deprived who become extremely low in mood. There’s quite a high risk of feeling suicidal just because I think it’s the difficulty where you haven’t got any control over the situation, you lose control and things are controlling you and you know that you’re due for the next attack. You know it’s coming back all the time, but I think it’s an incredibly difficult situation. You see, you know, people that you would have thought big tough men coming in absolutely reduced to tears. Women who can’t manage looking after their kids. You see people just really, really not functioning at all and really having a disastrous time where their mood is affected and I think there’s something even more biological about the mood because I’ve got about five patients, maybe six now who when they go into cluster bout they actually become psychotic. And they get proper good going psychosis and when they’re out of bout they don’t. One of those patients actually just gets psychotic during his cluster headaches.
00:43:47 Dr Katy Munro
Right.
00:43:47 Dr Nick Silver
Then, when he’s not in headache, he’s a chronic cluster headache sufferer. So I think there’s something about the biology and mood there that’s intrinsic, but also I think there’s something about the reaction and the impact of the condition that makes it very, very difficult for people to function.
00:44:05 Dr Katy Munro
I think also, these are also very often very desperate people who desperately want to get some help. And if they have diagnosis and they understand that they’ve got cluster headache, but sadly we hear that they often face a brick wall from people who are supposed to be helping them and they can’t get the prescriptions and they can’t get the oxygen, they do get very understandably, very frustrated, and that can then work against them because they start to be a bit shouty or hit the desk and kick off.
00:44:37 Dr Nick Silver
Kick off. Yeah, I’ve seen that so many times. I’ve seen that so many times and they actually get sent away from the surgery and told that they’re banished from that surgery or something. The agitation, the restlessness is the biological mark of their disorder. Maybe some of them are agitated anyway. But when you can’t get what you need and you’re in that desperate situation, I mean, people literally become, I mean, the word desperate can’t be highlighted enough. It’s a huge condition of desperation and they do need the treatments. It’s why I’ll regularly have discussions with GPs each week saying, you know, you need to give your patient fifty-six injectors of sumatriptan, 3mg.
And they go, we can’t do that and I’ll say, well, the NICE guidelines state that that’s reasonable, it’s ethical, it’s appropriate and it’s cost-effective to do that. Actually, fifty-six injections may only be two weeks prescription. And patients are really struggling, so they need that. The fact we can’t get oxygen, we’ll come on to this later. But the fact that we can’t get a demand valve for many of our patients which we’re really seeing anecdotally be far more effective than the non-rebreathing masks with oxygen. That’s really, really tragic and we’ve been trying to change the situation for over ten years with the National Health contracts and the way they contract oxygen and we’re just coming up against brick walls the whole time.
To the numbers of people in the country purely affected by a postcode lottery where they can’t get the treatment they need everywhere. You know, OK, we haven’t got rigorous control trial evidence to say demand valves are better. But when we look at patients, you know, it’s so blindingly obvious that there’s a huge difference with demand valves being not only safer but work far quicker, far more effectively in the vast majority of patients.
00:46:35 Dr Katy Munro
They’re less wasteful of oxygen as well, aren’t they?
00:46:41 Dr Nick Silver
Yeah, it costs less. It costs less. The whole situation is just bonkers, really. And I don’t get it. I’ve spoken to very high-level people at many different, you know, many different sides of what’s going on there. And we can’t seem to shift it just because of something written down on paper with a certain contract or two. And it’s crazy.
00:47:04 Dr Katy Munro
We maybe need ITV to do a drama about it.
00:47:08 Dr Nick Silver
Yes. Yeah, good plan.
00:47:10 Dr Katy Munro
Yeah, we’ll get the writers. We’ll contact the writers.
00:47:13 Dr Nick Silver
Oh, I think that would get a lot of public support. All you’d have to do is put a video camera into a few people’s houses and show what’s happening and then show what they could have. Yeah, ITV.
00:47:26 Dr Katy Munro
Yeah, we’ll do it, Nick. We’ll do it. So going back to what I was saying about benefits and PIP. I hear comments from people saying, I’m applying for PIP, but I have episodic cluster headache and so they apply and they aren’t eligible and they get rejected but then you know if they’re having quite frequent episodes and that can be so very unpredictable. It can have a massive impact and they can need to be supported by the benefits system and what they tend to say is that if you go back and appeal then quite often you get seen, you get to plead your case and often there’s also a doctor there who understands a bit more and then they get approved. It feels like a lot of things feel like a battle, don’t they, for cluster headache patients.
00:48:13 Dr Nick Silver
Yeah, I think this comes back. I mean, this again is a scandal that you could put through an ITV drama with the benefits system. Because I’ve yet to see someone lose an appeal on this. And yet on more than one occasion, I haven’t been there, but it’s been fed back to me that the judge said that this is absolutely ludicrous, that this patient has had to jump through this number of hoops to get to an appeal, and clearly there are problems with this. It’s a systematic failure to patients. This whole process of trying to recognise disability, you can have the strongest worded letter from a consultant specialist at a major leading centre and yet it’s completely ignored.
00:49:00 Dr Katy Munro
Yeah.
00:49:01 Dr Nick Silver
On a practical perspective, if people want to get help with this, then the two places I would suggest going to are The Brain Charity, which is a charity which is run out of Liverpool. And The Brain Charity will help patients with their PIP applications for neurological disorders. But particularly things like cluster headache, they’re very good in that. And the second place obviously is OUCH UK, which not only will help with certain areas of this, but they will also help provide emotional support. So not only the patients but also their families and their carers. That’s really, really important as well. So I think The Brain Charity and OUCH UK are two really useful places for patients to be aware of and their families.
00:49:47 Dr Katy Munro
We’ll put the links to those in the blurb for the podcast.
00:49:50 Dr Nick Silver
I’m just going to come back one second because we’re talking about the psychological effects and mood-related effects for cluster headache. I have never seen an antidepressant have any benefit to a patient with low mood with cluster headache. You have to treat the condition. You know, antidepressants aren’t going to have any role to play for this. Yes, patients need to sometimes be under community mental health team where there’s suicidal risk because there needs to be watching in place and needs to be plans, people need support, they need to have access to emergency help lines etcetera.
But pharmacological management and manipulation should be for the cluster headache, not the mood. I just don’t think that, and I’ve seen people go on high-level antipsychotics as well as antidepressants and all sorts of drugs. I just don’t think they have any role to play for the mood, you need to sort the condition out at its source.
00:50:43 Dr Katy Munro
We do see a lot of patients. We’ll come on and maybe talk about treatment now, because we do see a lot of patients who say, oh, my GP said it might be cluster headache and they gave me amitriptyline or they gave me propranolol. And I’m sort of slightly rolling my eyes, thinking, right, OK, there’s a bit of a muddle there about the diagnosis and the management. Acute treatments are very different. Can you talk about acute treatment, first of all? And sumatriptan.
00:51:10 Dr Nick Silver
Yeah. So in a similar vein, a lot of people are given oral triptans. And oral triptans, you put them in your mouth, you swallow them, and they go down into your stomach and they take an hour or two to be absorbed or whatever. I’m not very good on pharmacology, but they take a bit of time to be absorbed and then get into the bloodstream and then go to the head where the brain says, well, a bit bloody late, isn’t it? Excuse my language. It’s the brain talking. It wasn’t me, you know, it’s a bit late. It’s gone. So you’re constantly arriving late for the attack.
So oral triptans are no use. And nasal triptans, unfortunately for most patients, they’re used the same as oral triptans. If you read the package from them, it says tip your head back, spray. So what patients do is they tip their head back and they spray and they often sniff at the same time, which gets it nicely to the back of your nasopharynx and down into your gullet and down into your stomach, where it’s going to take an hour or two to get absorbed by your bloodstream and get round to the brain where the brain’s going to say, it’s a bit bloody late, no point.
So if you’re going to take nasal triptans and I think that the taste of – and I’ve got no affiliations for any company or anything else — but the taste of zolmitriptan is not as nasty as that of sumatriptan apparently, but you want to tip your head forward and you want to keep it forward for a couple of minutes and you don’t want to sniff. In other words, the drug is then absorbed through the lining of the nose, the nasal mucosa, and it gets direct to the bloodstream. You want a drug that goes straight to bloodstream quickly. And then it gets to the actual heart of where it’s going to act and have an effect.
So nasal triptans can be useful. I think there’s a specific instance where people are waking up at night from attacks and the nasal triptans again may not work quite fast enough. Subcutaneous sumatriptan injections are the gold standard, they work quickest. They get into the blood quickest, they have the best effect and the best proven effect. And for 90% of people, they only need the 3mg version of sumatriptan, not the 6mg subcutaneous injector.
So I’m really pleased we’ve now got that. I spent many years going to the drug company campaigning, saying please do it and then another drug company actually bought it out instead, which is some pharmaceuticals have the 3mg and 6mg injectors. Some people at night, when they have their attacks, the 3mg isn’t fast enough, and they might need a 6mg when they first wake from sleep with an attack. Because there’s a whole point about getting the right treatment in, the quicker you get in, the more likely it is to work. So maybe at night some people will use 6mg, but try the 3mg first, and if 3mg is good enough, that’s fine. They can always do another one, you know three or four minutes later, another 3mg three or four minutes later if it’s not working. So there’s always that option there with the 3s. And you should be allowed up to four of those a day.
So I normally start with the subcutaneous sumatriptan injections. I might give some nasal Zomig 5mg or 10mg if they’re going to maybe need it when they’re out and about and can’t inject easily or in the daytime. And my general adage is that I’ll allow them up to 10mg of Zomig and 6mg sumatriptan subcutaneous in a twenty-four hour period. There’s no real guidance as to how much you can mix together when you’re doing different ones.
00:54:29 Dr Katy Munro
Yeah.
00:54:29 Dr Nick Silver
But either it’s 15mg of Zomig nasal or it’s 12mg of subcutaneous sumatriptan or it’s a combination of 6mg sumatriptan and 10mg max of zolmitriptan. We might be going a little bit higher than is recommended there officially, but I think that’s a reasonable approach and as long as you have the discussion with your patient that these things are slightly, you know. not necessarily always exactly on-label. There’s not always exact 100% proof that this is going to be effective and safe. But we think it’s likely to be safe and that’s fair enough.
00:55:05 Dr Katy Munro
Do you advise people to take 10mg, so two of the zolmitriptan nasal sprays at the same time? Or would you say 50mg total spread out through the day?
00:55:18 Dr Nick Silver
It depends. If 5mg works effectively, then use it as a 5. But for some people the 10 is the only one that works and I’ve got a few patients who really want to be on the Zomig, not the injectables. Of course I’ve said, right, well up to 10mg twice a day then. So I will vary it and I might go above what the recommended doses are very slightly, but then we have patients who are so desperate that they will come in and you’ll hear that they’ve been using eight sumatriptan 6mg injectors a day.
I’ve had one patient who had a heart attack after using subcutaneous sumatriptan in my whole career and that did make me a bit nervous, but we don’t really think it’s got a highly vasoconstrictive effect. There’s very slight issues there, so I think just a little bit of caution, if you’ve got someone with unstable angina or a recent heart attack, I wouldn’t be giving the sumatriptan or Zomig. If I’ve got someone with very mild controlled angina, I’d have the discussion with the patient as to whether they want to do it or not. And obviously look at other options for acute attack. So just thinking about the other acute attack treatments, we’ve already touched on oxygen. Oxygen, high-flow demand valve, is anecdotally by far the best. We haven’t got research evidence, but anecdotally that’s by far the best.
They’re breathing in, it then triggers the release of really high flow oxygen, a bit like a, you know, gas and air device in labour. So that would be optimal. If you’re using a mask you want to use a non-rebreathing mask which has valves on it. You’re not having room air coming in with it. It’s not mixed. It’s still 100% oxygen and you want it up at twelve to fifteen metres a minute. And you don’t want to be using it for too long. If you’re going to use oxygen, you don’t want to be using it for more than, say, twenty-five minutes. Otherwise you get what we call tachyphylaxis and it stops working. And then people get a lot of rebound headache and it gets worse. So I think oxygen can be really helpful. The demand valve in particular, but it’s cumbersome to cart around.
You need good safety advice with oxygen. Can smokers have oxygen? Which is a question which people are going to ask. There’s no rule saying that they can’t for cluster headaches. It’s only COPD that they say they can’t. And in COPD, they’re stuck with their oxygen. They’re on it for maybe eighteen hours a day or more. And they therefore can’t leave the room to go and have their cigarette, and I will always say to patients, and I’ll back this up with further things, but I’ll give them an information pack. I will say to them that I’m only going to give them oxygen if they absolutely assure me that they and everyone else in the house will only smoke outside of the house.
And certainly the room with the oxygen, it shouldn’t be kept in direct sunlight. It shouldn’t be kept next to radiators or heat sources. It shouldn’t be supplied next to supply, so kept near flammable products like paints and face creams. I tell patients not to use skin creams on their face when they’re using oxygen because it makes them more flammable. And they shouldn’t go near a naked flame or spark or vape or cigarette within half an hour of using oxygen, because their skin and their hair are more flammable. So I try and give quite a lot of advice around safety. Make sure it’s followed up by the home oxygen service and the fire service going and giving advice.
Yes, all mitigating features taken into account, I don’t like giving oxygen to smokers, but it is something I will think about, but I will generally go for triptans first if I can.
00:58:58 Dr Katy Munro
But the other thing about oxygen is that it varies very widely over the whole of the UK as to who is allowed to prescribe it. So in some areas we’re finding that GPs can fill in the HOOF form and they can get not only home oxygen cylinders, but they can also get portable oxygen cylinders and they will do that. In other areas, the GP says no, I’m not allowed, I have to refer you to the respiratory care team.
00:59:18 Dr Nick Silver
Oh, OK.
00:59:27 Dr Katy Munro
And in other places it’ll be the consultant neurologist. So it’s a real postcode lottery again. And the battles are really real for oxygen, aren’t they?
00:59:33
I don’t know how much of this is genuine or not because we get GPs in our own areas in Liverpool saying we’re not allowed to prescribe it. I know they are and there is a HOOF part A and a HOOF part B, the HOOF part A is for GPs and it’s for fixed cylinder. Admittedly it only gets an emergency supply in the sense they only get a big fixed cylinder or two fixed cylinders. When we’re doing a HOOF part B I often give three large and three small portable ones. I might give less if the patient wants less. The costing for that, I don’t know if it’s still the case, but it always used to be that the costs incurred were those of replacing cylinders, not the amount of oxygen that’s used. So actually having a large number of cylinders at home that aren’t necessarily all being changed all the time wasn’t incurring costs, but it gave the patient what they needed when they needed it.
01:00:28 Dr Katy Munro
There are several different oxygen supplying companies as well, aren’t there, around the country. I’m aware of there’s at least four.
01:00:33 Dr Nick Silver
So some like, for instance, Baywater won’t give a demand valve in the region I work in for a lot of it, but they will in other areas that they serve. And this is all down to the way that each individual contract has been written. It’s about words. What we really want is I would like some government minister to actually look at this and just say this is absolutely nonsensical, ludicrous rubbish that’s basically disadvantaging our patients on a postcode lottery. That’s what it is. This isn’t political, but it needs someone at the Department of Health to actually properly just recognise we’ve been trying to get this across for years. No one is listening.
And the patients, you know, there will be patients out there, like the post office scandal, people committed suicide in the post office scandal. Unfortunately with cluster headache, also known as suicide headache, we do see patients committing suicide because they have not got what they need. And these are potentially preventable suicides. It’s rare, thankfully. But, but a lot of people are living on the edge of suicide and you just would have thought that something could be done.
01:01:54 Dr Katy Munro
Yeah. Yeah, going back to what you were saying about sumatriptan injections, the other thing I hear sometimes from patients is that sumatriptan often makes them feel really groggy, and so they delay using the injections and try and push through and then they eventually may or may not use it and so they prefer the nasal sprays or they prefer the lower-dose injections. So this is because the 3mg and the 6mg injections are actually the same price, I understand the GPs, and there’s no incentive for GPs to prescribe the 3mg because they’re not any cheaper, they’re just the same price. If you’re almost paying double if you pay the 3mg.
01:02:41 Dr Nick Silver
But it actually becomes much more expensive. It becomes much more expensive because GPs are then able to give four injectors and that actually has double the cost of using two injectors. But it depends on what the patient’s frequency of attacks are and again where they are in the bout. They may come at the beginning of the bout where they’ve just got two attacks a day. But in their bouts in the past or in this bout, they may go up to five attacks a day, or four attacks a day. So I think we need to be flexible and I think patients do need to know that they don’t have to fight for it each time. And it’s very, very hard when they have to fight for this, I think it’s really difficult.
01:03:22 Dr Katy Munro
Yeah, makes a horrible condition even harder to deal with when you’re thinking I’ve only got four injections to last me for the next– like, you know, they’ll be gone in a day.
01:03:35 Dr Nick Silver
We’ve talked about acute treatments with oxygen and triptans, but we haven’t mentioned other acute treatments and one of them that’s out there which should be available to patients in the NHS if they have not responded favourably enough to oxygen or triptans, is gammaCore vagal nerve stimulation. And hospital neurologists should be able to prescribe this, and I suspect that certain GPSIs will be able to prescribe it. If it’s not possible to get it, even on a short-term basis, people can buy it and they can get it through electroCore. It’s about £100 a month, so it’s not cheap, but it can be effective in episodic cluster headaches to treat the acute bouts of headache.
01:04:21 Dr Katy Munro
Describe it a bit, Nick, because people may not know what a gamma device looks like. It’s a neuromodulation device, isn’t it?
01:04:30 Dr Nick Silver
Yeah. So gammaCore is a vagal nerve stimulator. It’s a handheld device. It’s probably the same size as an old mobile phone before we got smartphones. It’s got two little metal prongs on the ends, little rounded areas which you put a bit of gel on. You place it on your neck next to the windpipe and you stimulate it for two minutes at a time. Now the company will suggest that you use it two stimulations three times a day. I actually recommend you use it three stimulations, three times a day. And we’ve got some evidence from the clinical trials, randomised controlled trials, that it may be effective in episodic cluster headache.
And that was looked at versus sham. So in episodic bouts of cluster headache, where you’ve got someone actually going through a bout it tends to work in the acute attacks. In the clinical research, it couldn’t be proven that it works for acute attacks when people have chronic cluster headache. But you have to be aware that a lack of proof in a trial doesn’t mean a lack of response in a patient, and we still see some patients who benefit from it acutely in chronic cluster headache. Although it seems to be more effective in episodic cluster bouts than chronic when used actually for the attacks. you use it as quickly as possible, you’d use it for three stimulations, and if you’ve still got the headache, you do another three stimulations. So you’re talking about six minutes to start with. three lots of two minutes each, and then you might do another six minutes. So that can be an effective acute attack treatment as well as being a preventative treatment. Then we’ve got the research evidence to show that it is helpful as a preventative. We find anecdotally that it may be useful in preventing in about 50% of patients with cluster headache who have particularly chronic cluster headache. And in our hospitals we have a pathway which allows us to use gammaCore if they’ve failed to respond to oxygen or triptans effectively enough in acute attacks or as a preventative if they’re failed to respond to verapamil or nerve blocks which we’ll come on to in a minute. So I think that’s the third option for treatment of acute attacks that’s worth considering out there.
And then we’ve got some more weird and wonderful things. Different nasal sprays and hormonal treatments, which I don’t think any of us really use these days. Things like octreotide and lidocaine nasal sprays and I don’t think they’re the best option, really.
01:06:59 Dr Katy Munro
Not really helpful. So let’s talk about nerve blocks, because I know there are some patients who as soon as they start having their bout, they book in, they get their greater occipital nerve blocks. And it seems to just nail it.
01:07:12 Dr Nick Silver
Yeah. So I think if we just go back one step historically before we started using nerve blocks a lot, we used to think of three types of treatments for cluster headache. There would be acute attack treatment, which is a section we’ve just covered. We would then have preventative treatment, which was split into two groups and we had the transitional preventatives, which were things that we could use short-term to help people, and in the longer term preventatives which have a continuing ongoing effect.
So the traditional short-term preventative, the transitional preventative that we used to use was a reducing course of steroids. Works probably in somewhere around 80 to 90% of patients. You give them 60mg prednisolone, you reduce it every three days by 10mg until stopped. And it may be effective, but it’s only effective at the time that they are taking the steroid at a dose above their threshold dose that they need.So for some people, they need to be above 20. For some people they need to be above 40mg. For other people, they need to be above 10. It will be the same in that person for each bout, but it has no useful effect long-term. It’s only useful while they’re using it, so you might use a transitional treatment while you’re getting something else in place that’s going to work. For instance, escalation of verapamil, which we’ll come back to in a minute.
01:08:30 Dr Katy Munro
Yeah.
01:08:30 Dr Nick Silver
So I just wanted to mention steroids. But the other one that we started using as a transitional treatment and in fact if anything, it’s taken over for many patients, it’s taken over as a preventative full stop for episodic cluster headache and for our patients with chronic cluster headache is nerve blocks. I’ve spent many years having originally taught myself how to do nerve blocks because I couldn’t find anyone to teach me, and no one seemed to know how to do the more widespread nerve blocks.
I basically have experimented on hundreds and hundreds of patients to try and find out what the best combination is and what I’ve settled on is to do a greater and a lesser occipital nerve block. There are two nerves going up the back of the scalp. The greater and the lesser occipital nerves. These are part of the wider system that sends signals into the trigeminal system, so you’ve also got your third occipital nerve at the back, which is a tiny nerve. You’ve got your preauricular nerve in front of the ear. You’ve got your supraorbital and your supratrochlear nerve above the eye. And these all send signals in, presumably to the trigeminal networks and neuromodulatory. So by blocking them with local anaesthetic and potentially with a small dose of steroid. And we can talk about that in a second. We can modulate the headaches and turn them off for a period of time.
And nerve blocks for most people, when they’re used, work straight away. I’ve got some patients who it might take two or three weeks for them to kick in, but for the majority it works straight away. And I’m not talking about the numbness that they get for a day or so or few hours or so. That’s separate. I’m talking about the potential, once the numbness is settled down to still prevent attacks occurring or reduce them in huge amounts, so then they’re normally extremely effective when they work. So I would normally start with a greater and lesser occipital nerve block. If they’re no better within a week, I’d bring them back or I’ll get them to call up, bring them back up, and I’ll do a multiple cranial nerve block where I’ll do all of the five injections on that side of the head. In our hands and in our experience, nerve blocks for episodic and chronic cluster headache probably work somewhere between 50 and 75% of people as a sole treatment a highly effective sole treatment.
01:10:52 Dr Katy Munro
So what are you injecting into those sites?
01:10:55 Dr Nick Silver
Yeah, so I use long-acting bupivacaine and I use high volumes. And I think that’s a really good question because a lot of places say, oh, we don’t really use nerve blocks because they’re not very effective. And when you look at what they’ve injected, they’ve used tiny volumes of short-acting, local anaesthetic. Some patients say that they need the steroid for them to work and they say without the steroid it doesn’t work. We haven’t really got any double-blinded controlled trials to know what’s true and what’s not true there, what’s placebo, what’s real.
But we have got some patients who seemingly need the steroid and some patients who don’t. I think it’s really interesting to know where they’re going to work, where the site is, so we start with occipital nerve blocks for a headache that’s predominantly frontal and around the front of the head in a different nerve distribution. And for a lot of patients, they work. There are a group of patients that say, do you know what, the back of the head was great, but the headache just pushed forward and I never really noticed it at the front, but now it’s really occurring at the front. So I think for a small number of people, it’s anatomically relevant where you inject.
But for a majority, injecting at the back of the head will help a headache at the front of the head. OK, so I would start with the greater and lesser occipital nerve block, and then I go on to multiple cranial nerve block. We generally see responses on average between, say, two months and six months for cluster headache.
01:12:05 Dr Katy Munro
Right.
01:12:19 Dr Nick Silver
I’ve got some patients who go on further and I’ve got one patient who I just contacted me a couple of weeks ago who has a nerve block every three years for chronic cluster headache and it just wears off. Literally. It’s the same each time. She’s been coming every three years for these for years and years and years, and it wears off and you see it gradually coming back. And she has a nerve block and it’s gone again on that day. So it’s a variable amount of duration of time that they work for, but the majority of between about two and six months for cluster headache, maybe a bit longer in some, maybe up to eight months and some are even longer than that.
01:12:53 Dr Katy Munro
And when you say large volumes, what is a large volume?
01:12:58 Dr Nick Silver
OK, so I will use up to 20 to 22mls of 0.5% bupivacaine, per session, and you can do that as often as you need, but we don’t do it more often than every three months generally. I mean, maybe someone who’s pregnant and we’ve got no other options we might do it every two months. With the steroid, I use Kenalog and I don’t use more than Kenalog at any session. I try and use less than that so for cluster headache I would use half a ml of Kenalog. I only inject the Kenalog, the steroid, posteriorly because it can cause skin indentation or with lipoatrophy or a small patch of hair loss. That’s rare. Less than 1 in 150 9in the literature, much less than that if you use low doses of steroid such as I’ve just described. 0.25mls of Kenalog, which is basically 2.5mg of Kenalog. I would use that per injection, so that would be for the greater and then I’ll do the same for the lesser occipital nerve. But because it can cause those side effects on the skin and dimpling, I won’t use it in front of the ear or above the eye. I don’t want to cause cosmetic effects.
But I try and use the smallest amounts of steroid possible to avoid problems, but I think high doses of long-acting local anaesthetic are helpful. So in my recipe, a typical multiple cranial nerve on one side would have each of the occipital nerve blocks would be 2.75mls of 0.5% bupivacaine with 0.25mls Kenalog. And then I might use somewhere around 6mls to 7mls around the preauricular nerve, which is quite a difficult one to anaesthetise because it’s quite variable where it is in terms of depth, and I’d use just about 2mls, probably in the supraorbital and supratrochlear, I do them on a single needle and I just move the needle slightly medially to get the supratrochlear nerve.
So for those of you watching in black and white, it’s quite hard to follow what someone’s doing, but if you know where I’m injecting, I mean, the supraorbital and supratrochlear is basically an injection in the eyebrow, you’ve got your orbital notch. The preauricular is just in front of the ear and the greater and lesser occipitals I don’t think are quite as people say in the textbooks. I think they’re about one centimetre. If you take a line between the mastoid process and the base of the skull at the back, the centre, then you’ve got about one centimetre to one-and-a-half centimetres out is the greater occipital and I think the lesser occipital is halfway between those two.
I’ve spent many years injecting in different places and I think that that recipe tends to get them and I always check sensation after I’ve done it. I check pinprick and the other thing with my nerve blocks is I massage them in really heavily, so I really make sure they’ve got really good massage around those areas to make sure that they’ve got good effect. Now, I don’t let someone out of the room until I know it’s blocked and they’ve got an anaesthetic effect of some sort.
01:16:00 Dr Katy Munro
Excellent. We always also get asked, is there any point in having Botox for cluster headache?
01:16:09 Dr Nick Silver
Yeah, there’s very limited data for Botox. We’ve sometimes done it in patients who are maybe being worked up for occipital nerve stimulators where we would try that just as a lesser invasive option.
I think where Botox works and what we didn’t mention before in terms of the headache, we talked about episodic cluster headache happening in episodes, but 30% of people will have a background headache on that same side, which is sort of more migrainous-type headache. And then people using a lot of triptans will have a background bilateral headache from medication overuse, which they’ll put with. It makes them tired, neckache, dizzy, can’t concentrate, all the features you get with medication overuse headache or migraine.
So those patients may benefit from the Botox. The Botox tends to get the background headache much better. I don’t think, for the majority of patients it doesn’t have much effect on the cluster headache, frequency or severity. From an anecdotal point of view, there are a few patients that I see who it does help from the cluster headache itself, but the majority, it helps the background headache in that 30% or those with the rebound, medication overuse headache.
01:17:22 Dr Katy Munro
Right. That’s interesting. Yeah. So we’ve covered the bridging transitional therapies, I think now, haven’t we? So what about prevention? You’ve mentioned verapamil, I know that’s usually considered the gold standard, but it comes with some cautions.
01:17:40 Dr Nick Silver
Yeah. So verapamil used to be considered the gold standard, I personally think nerve blocks are the gold standard now. I think verapamil might work in more people, but I think nerve blocks can be particularly useful. Patients can go away. They don’t have to think about their condition. They’re much better. They’re not having to have regular ECGs. I personally think that investing in nerve blocks is really, really helpful, especially considering multiple cranial nerve blocks where the occipital nerve blocks have not been effective enough. When we inject multiple cranial nerve blocks, they tend to work more effectively, and they tend to work for a lot longer than the occipital lobe block. So we get that extra benefit of the duration of benefit as well.
So in our Walton Centre pathway, we start with nerve blocks. So we start with nerve blocks, start with greater and lesser occipital nerve blocks, I go onto multiple cranial nerve blocks. If that doesn’t work, then officially we’re supposed to go on to varapamil and then gammaCore. One of the difficulties with verapamil, particularly over the pandemic, was lack of access to getting people in for ECGs and trying to send people out with the schedule to primary care saying “do an ECG every two weeks and increase it every week” invariably doesn’t get done, and patients are out there not being monitored appropriately on high doses of verapamil. And then we see people with heart block and other complications.
So I’m not that comfortable about verapamil in primary care. We do it sometimes, but I think it’s very hard to get it optimal. I think I’d rather see it under my own jurisdiction and where I can actually see the ECGs and know that what I’m doing in this unlicensed high dose is safe. So my personal view is that if they haven’t responded to nerve blocks I would normally go for gammaCore next.
01:19:33 Dr Katy Munro
Uh-huh.
01:19:34 Dr Nick Silver
If they’re in chronic cluster headache, I would go for gammaCore next. If they’re episodic cluster headache I might go for gammaCore next as well. gammaCore can take a bit of time to work, so there’s a decision to make as to whether gammaCore or verapamil will be my next line and I have to think about a few factors there as to which I go for.
01:19:53 Dr Katy Munro
Mm-hmm.
01:19:53 Dr Nick Silver
If I’m going for verapamil and if I’ve got the access to that, then I would start with the immediate release formulation because it’s said to be better tolerated than the slow release. I’ll start with 80mg three times a day if an ECG is satisfactory. On the ECG, I’d be wanting to check there’s no signs of heart blocks, so I want to see that the rate is greater than 45 beats per minute. The PR interval is less than 200 milliseconds. The QRS complexes are not broadened. There’s no obvious evidence of ventricular conduction block there. I want to see that the axis is normal with leads one and two, both predominantly positive, and then I would personally go up by 80mg every week in TDS fashion, so 80mg TDS and 80-160, often targeting the nighttime dose as the highest dose because that’s when most people have their attacks, and I’d keep going up by 80 every week, ECG every two weeks. And if patients obviously get breathless on exertion, that’s a left ventricular dysfunction. They need to reduce dose down again. If patients get a prolonged PR interval but they’re getting a good response to it, I might stay on it. But do a 24-hour ECG to ensure that they’ve not got any evidence of runs of complete heart block. And I’ll keep a close eye, so my general adage is that for people on 480mg or less than 480mg verapamil a day I’ll do an ECG. Once they’re up to that dose and it’s all working well, I’ll do an ECG every six months. If they’re on more than 480mg, I’ll do an ECG every four months. If they’re right up at the top levels of sort of, you know, getting up towards 880-960mg, I will do a 24-hour ECG every year as well just to make absolutely certain we’re not missing things. I warn people that if they’re taking any new drugs on verapamil, they speak to the pharmacist first, particularly antibiotics, which can cause really severe rhythm disturbances in combination with verapamil. And I never combine verapamil with lithium because that gives you a lot of toxicity with the lithium.
01:22:04 Dr Katy Munro
So verapamil can be amazing, but it comes with quite a lot of intervention needed from the monitoring clinician, whoever that may be.
01:22:30 Dr Nick Silver
Yeah, absolutely. So you’ve got your side effects, which you just reassure patients on. If you get some ankle swelling, that’s expected, and how bad is your ankle swelling? How good’s your cluster headache? Let’s get the balance right. Constipation, I warn about right from the beginning. I’ll often recommend that the GP gives a good supply of Movicol so that they take that on a regular daily basis, which is a safe thing to do. And if they get breathless on exertion, they’re on too much, it’s left ventricular dysfunction, they have to come back down on the dose. If they were getting a really good benefit, they might just come back one level to get the balance between benefit and side effects right. Obviously if they’re developing prolonged PR interval, there’s a little wiggle room there to keep it there or go up a tiny bit, but as long as you’re monitoring closely with 24-hour ECG. And that’s basically verapamil monitoring in a nutshell.
01:23:12 Dr Katy Munro
So the other medical options that I’ve come across people using is topiramate and lithium, and there are others as well. Those are very much by the sound of it, for you, those are very much fourth or fifth line, not first in most people.
01:23:32 Dr Nick Silver
I hate topiramate. And I’ve said this right from the beginning of using topiramate in migraine many, many years ago, I was saying, look, I’m seeing 80% of people get side effects and everyone’s going no, no, the literature in epilepsy shows it’s just 20% and actually we’ve now got literature showing it’s 80%. And it’s often very subtle. Well, it’s not subtle to us when we see a patient on topiramate, you know they’re on topiramate before they’ve told you, because it’s like talking to someone while they’re on their mobile phone. Everything is delayed. You know, it used to be talking to someone when they’re in Australia on a call and it was all delayed. Now it’s talking to someone with a mobile phone in their hand. They’re looking and they’re distracted. They’re not answering the question. Everything’s a question out. It’s just, urgh. And I think topiramate causes loss of insight. So you tell people all about these side effects, they go off and take it and then they come back in and they go, oh yes, you did tell me.
And it’s just so, so frustrating, and I mean it does work in some patients. I’ve seen quite a lot of kidney stones on topiramate as well. And again when I put people on topiramate, I have regular monitoring. I have six-monthly electrolytes. I have a yearly abdominal X-ray for calcium containing renal calculi or ultrasound. I do that as a matter of course. And then topiramate in women, we’ve got to be really cautious now because of the need for ultra-effective contraception on it.
I’d go for lithium after verapamil as my next line. Lithium sounds very frightening because we tell people so much, but because we tell them so much and we monitor so closely lithium’s a really safe and effective drug, as long as you follow the rules on it and as long as you monitor people. Be aware that you’re going for a drug level between 0.8 and 1mmol/l, but most patients can’t tolerate that. So once you’re up at 0.8 just be aware that they’ll start getting side effects most commonly, so you might be getting a level of 0.6, 0.7, that’s fine, but you get them up to highest level they tolerate. But just be aware that they’re going to get toxic side effects even when they’re, you know, they might have a level of 0.4 or 0.5 and it’s lower than the range we’re aiming for, but they can still be toxic on it, so just be aware that the blood level doesn’t actually indicate necessarily what you’re seeing clinically on that patient.
I’ve seen a few patients get epileptic seizures on lithium, which is a worry. You can’t use it in someone with hypoadrenalism. It’s got a long list of con meds, contraindicated medications that go alongside it, so you’ve just got to be really, really careful, especially with anticonvulsants alongside it. So I think as long as you know what you’re doing with lithium, it can be an effective drug. And it can be a very well-tolerated drug, but you need to watch people and you need to have the proper caution. And then just to–.
01:26:39 Dr Katy Munro
Yeah, go on.
01:26:41 Dr Nick Silver
Before we get to the new kids on the block.
01:26:43 Dr Katy Munro
Yeah.
01:26:44 Dr Nick Silver
There are a lot of other drugs that we will run through. So high-dose melatonin 10-15mg at night. Patients can buy that from Biovea online pharmacy, and you take it for a month to see if it’s effective. If it’s not, there’s no point continuing.
Sodium valproate, it’s got its issues with fertility and other things and affecting unborn children of potentially men as well as women, now we think. So sodium valproate I think can be quite effective. High-dose pizotifen, if it’s tolerated, can be quite effective.
There are other drugs that we will use. High-dose gabapentin’s – I don’t like, they’re quite addictive and I don’t like using high-dose gabapentin or pregabalin. We might use lamotrigine for some patients. So there are a lot of things that we try. The evidence for these is really small. I mean if any at all, it’s there for verapamil. Lithium, it’s hardly there. It’s definitely there for gammaCore, and although some people would say that the evidence is not of, you know, high-level quality. It’s definitely there for some of the stimulators, which we’ll come on to in a minute, I’m sure.
01:27:57 Dr Katy Munro
Yeah.
01:28:01 Dr Nick Silver
Implantable stimulators, and then you’ve got the new, I think you’re about to say, new kids on the block, like Botox and CGRP monoclonal antibodies. So we’ve talked a bit about Botox. I don’t think it’s really got a role to play, but I would trial it if I’m running out of other options before I consider occipital nerve stimulation.
There is some data on CGRP monoclonal antibodies, particularly for galcanezumab, which was shown to work with episodic cluster headache in the trial, but it hasn’t really been shown to work in chronic cluster headache.
01:28:36 Dr Katy Munro
Yeah.
01:28:37 Dr Nick Silver
So there’s some data for episodic cluster headache — the FDA say yes for episodic, but not for chronic. European Medicines Agency says no for both. There’s not enough evidence for both, so we’ve not got it licensed in the UK for any cluster headache.
I mean, the data on galcanezumab for episodic looks reasonable, you know, and I think it’s certainly something to consider. I mean it’s a complicated area. We’ve had failed trials. Fremanezumab’s failed a couple of trials. Eptinezumab, the intravenous one, has failed. You know, when I say failed they’ve been pulled part of the way through because they’ve realised that the preliminary data showed futility in continuing.
So eptinezumab and fremanezumab have both been pulled from studies. I think there was some small open-label studies that are still going on. So I think it’s still watch this space. But I think it’s very disappointing that we’re not seeing the sort of responses we’d hope for from CGRP MABs, compared to migraine
01:29:44 Dr Katy Munro
I guess if people have a dual diagnosis of migraine and cluster headache and they’re about to start one of the monoclonal antibodies. Then it makes sense to choose the galcanezumab in the hope that may have some benefit for both rather than going for the ones where there’s absolutely no evidence at all.
01:30:06 Dr Nick Silver
Yeah, that is an approach that I’ve tended to take. I know that NICE say once you’ve tried galcanezumab, you can’t use another one, but BASH, the British Association for Study of Headache put out a statement saying we don’t actually think that’s clinically appropriate. So I think most people feel supported by BASH in this country to say, look if I’ve tried galcanezumab and I’m really running out of options and we’re going to be looking at what’s the next step, maybe implants, blocks, occipital nerve stimulation, of course I’m going to try another CGRP first. You know, it’s clinical common sense, so.
I think galcanezumab first line for cluster headache’s reasonable, as you say, you’ve got a lot of patients there who are using a lot of triptans and getting medication overuse headache. And interestingly, we’re seeing that the CGRP monoclonal antibodies potentially work in medication overuse headache, so it does make sense where you’ve got especially a bilateral background headache or even a background continuous one-sided headache. I think the CGRPs make sense and you can — I’m not saying fiddle the books — but you can make a play that the patient’s got migraine as well. It’s a little bit of a dodgy thing to do but at the end of the day I don’t actually care about that side of thing. These guidelines are supposed to support us in doing the right thing for our patients.
01:31:23 Dr Katy Munro
Yeah.
01:31:23 Dr Nick Silver
But what comes first and foremost is do the right thing for your patients and as long as we’re not spending excess money doing something that’s got no evidence and is crazy, you know what we’re doing here has actually got evidence to support it, and I think that’s reasonable.
01:31:39 Dr Katy Munro
And I think real-world use of medications is also very useful and people are often collecting data about real-world use rather than just relying on studies. And that can be helpful and inform our clinical decisions as we go forward, can’t it?
01:31:54 Dr Nick Silver
It’s really interesting to see. I mean, you mentioned real world and just going to migraine and you look at the data. I remember the data first being presented on the CGRP monoclonal antibodies for migraine and thinking everyone’s going, oh, this looks brilliant, isn’t this great, look at their work and I was thinking, yeah, but look at the numbers. You know, good placebo responses, slightly better for the active group, it’s really minimal.
You will know, Katy, and you will have seen lots of patients now they’ve gone on these drugs, the MABs for migraine, and it’s been hugely life-transforming even in patients where, even, you know, a lot of patients unfortunately are labelled as carrying psychological baggage, a lot of it, with their migraine.
And we see everything switch off. You know, it’s not psychological. It’s part of the headache disorder. It’s not psychological, it’s real. You know, all the other side effects they get, but they came in wearing dark glasses. Yes, they’ve got photophobia. You know, all these markers that doctors used to use to label people as psychological. It’s just such a load of rubbish.
01:33:01 Dr Katy Munro
Yes, I agree.
01:33:03 Dr Nick Silver
Yes, these things get you down and they get you depressed but actually if you turn off the condition at source then actually funnily enough the depression goes and the cognitive function is back to normal, and it’s what we see with episodic migraine. You see someone in episodic migraine, their brain is turned into mush, they can’t concentrate, they can’t think, they’re very depressed. And yet two days later, they’re absolutely perfect again. And I think, it’s very unusual to see a medication that in real life has way surpassed our expectations from what we saw on the clinical trials. And so I think that that sort of viewpoint that we have and our experience does tend to make us want to try these things when we see someone in such a desperate state with cluster headache.
01:33:52 Dr Katy Munro
Well, we deal with individuals and studies deal with populations. And so if you look at a population and you average out the response, you may get a very much sort of average zero, nothing very much happening. But if you look at the individuals within that population, you may get some super responders, some partial responders, and you see some people who don’t respond at all. That doesn’t mean it’s no use.
01:34:16 Dr Nick Silver
And that’s really clear with the galcanezumab data. When you look at the data from the responders, those who actually had a 50% or greater responder rate. And you compare it. I mean 71% of patients with galcanezumab for episodic cluster headache, admittedly small numbers in the trial, it’s about fifty versus fifty or so, but 71% have more than 50% reduction in their number of attacks per week. Now admittedly there was a very high placebo response of about 50% in that trial.
But placebo is great. I mean, I’m happy with placebo because in real life that is our patient much better.
01:34:58 Dr Katy Munro
Yeah, absolutely.
01:35:00 Dr Nick Silver
So you know, as long as we’ve got a drug which has minimal if no adverse problems and you know the CGRP MABs are highly targeted, we’re not seeing any signals for any worrying problems from any of them. And they’re extraordinarily well-tolerated, possibly a bit of constipation, possibly the occasional person with a slightly higher blood pressure, but that’s about it. I mean, it’s a no brainer to think about these drugs.
01:35:27 Dr Katy Munro
Yeah. You mentioned the implanted nerve stimulators. So that’s something obviously in the National Migraine Centre, we don’t get involved with that sort of thing. We would definitely be referring on if we felt that somebody needed that sort of thing.
01:35:41 Dr Nick Silver
You don’t tend to stick them in yourself in your clinic?
01:35:45 Dr Katy Munro
Funnily enough, no. So what I understand is that is only appropriate for certain very hard to manage people. Well, the people aren’t hard to manage, but the headaches are hard to manage, the cluster attacks are hard to manage.
01:36:01 Dr Nick Silver
Yeah.
01:36:02 Dr Katy Munro
Only people with chronic cluster headache who would have those?
01:36:07 Dr Nick Silver
People have been implanted with episodic cluster headache, but it generally is a chronic cluster headache, ones that end up with that because most of the episodics we can manage and they get respite between their bouts.
Yeah, I think it reminds me a bit of the debate we’ve had with trigeminal neuralgia. Well it’s not really been an open debate. It’s a debate that goes on in our practice all the time and basically you try these drugs on people that make them feel lousy. And how many drugs do you have to go through before you actually do something definitive like a microvascular depression for trigeminal neuralgia? That sorts them out. Are we right in putting someone on drugs that are going to make them not concentrate, that are going to give them adverse effects, that are going to make them dopey for years?
And the same thing goes with cluster headache and implantable stimulators. You know, to go through ten to fifteen trials of drug preventative therapy, maybe Botox, two or three CGRP monoclonal antibodies, bringing them in for intravenous dihydroergotamine, the different types of nerve blocks, the vagal nerve stimulators — to make them jump through all these hoops and then turn around again. Yes, admittedly, 95% of people or 90% of people we’ve sorted out, but it does feel that when we’ve got those patients, when they’re coming to occipital nerve stimulation, I’m sure there’s data out there. I’m sure someone like Prof Matthew would have got some data saying how long people have waited till they get that, how many treatments they would have had.
01:37:41 Dr Katy Munro
Yeah.
01:37:41 Dr Nick Silver
But once we get to that group, we do feel, have we let you down? You know, we’ve been trying to treat you for ten years or fifteen years. And should we have gone to this sooner, and it would be nice to be able to predict who we’re not going to get any response to, and know this. It would be nicer if we have sort of lesser invasive devices or things that are easier to do, you know, better hardware, better longevity, not needing recurrence procedures.
And we got really excited by the sphenopalatine ganglion stimulator that was produced by ATI, Autonomic Technologies. They unfortunately went bust a number of years ago and so we’d seen good randomised controlled data for SPG stimulation. A little device. There’s no implanted battery. It’s all Bluetooth or equivalent. And not only was it helping to treat the acute attacks, but it was also started to show some really significant preventative effects. So we were getting really excited. We were starting to use that in the UK and then it had problems. Reassuringly, to some extent, the company has just got a new, I think it’s been bought again or someone has– I just see that a company has taken this on again, but I’m not sure whether they’re focused on cluster headache or looking at this as a treatment for other conditions, but I think it is a watch this space.
Because I think that treatment had a lot of promise. It involved centres with a lot of experience doing it because I think there was a really good learning curve that the more people were implanted, the better your results were.
01:39:30 Dr Katy Munro
I was seeing how is the patient done, through the mouth, am I right?
01:39:34 Dr Nick Silver
Yeah, it’s done under the lips so it’s done intraorally, and you basically, if I remember rightly, you drop the top palate down and you go in up under the top palate. So that’s the sort of way in. So I mean, it’s quite a fiddly procedure and before it you’d make a 3D printer model of someone’s skull and facial bones so you can see exactly where you’re putting it.
It does beggar the question as to whether we should be looking at more SPG-derived, you know, should we be doing SPG nerve blocks? And again, I think we haven’t as neurologists, we haven’t got quite the confidence to be going forward with those and knowing we’re putting them in the right place. There are some devices that can help guide your local anaesthetics the right place. Some people just use a blind approach, I haven’t done those myself. Some people look at using SPG Botox, where you’re just basically injecting Botox around the area near the SPG ganglion, and that’s got some data for it as well. So I think the SPG is a good target, it needs to be brought back in. We need to be training up how to do it for nerve blocks and possibly Botox and hopefully the stimulator will come back in. And the reason I’ve mentioned SPG in advance of occipital nerve stimulation is that whilst occipital nerve stimulation is much more tried and tested and has been there for longer, occipital nerve stimulation hasn’t got the data behind it that SPG simulation had.
And the kit has really been the problem. For a period of time. there was a rechargeable occipital nerve stimulator called a Bion device. And that disappeared, where people would recharge it by lying on a certain type of recharging pillow. And it would just basically be a little device at the back of the scalp and that had a lot of promise. And I think people are starting to look at companies like Stimwave to see whether these Bluetooth devices with little tiny strips are better or can give you the same sort of thing as the proper occipital nerve stimulator, which is a kit which attaches to a pacemaker-like device which is either in your chest wall cavity or your abdomen or over your buttock. The problem with the implanted occipital nerve stimulation with the implanted battery is that the battery runs out. Or if your leads are too far away from the nerves and you’re using too much electricity and it runs out faster. Or people get infection, or the leads, or the device start to erode through skin. And again there’s a really big learning curve, and if people are having that done, they are best to have that done by a centre that does a lot of them, somewhere like Queen Square London is. It’s got one of the best centres for that worldwide.
01:42:30 Dr Katy Munro
Yeah, yeah, yeah.
01:42:31 Dr Nick Silver
We do them in the Walton, but I don’t think we do as — I’d like to see us doing more and getting better at it. I think we do them all right. But I think that London has the best experience at the moment and then there are other centres in London that will be doing those as well.
So I think occipital nerve stimulation can be really effective for patients. It can significantly reduce the frequency and severity of the attacks. But it comes with a warning that you may need repeat surgeries. And it’s obviously more invasive, but is that better than waiting fifteen years without hell and not having control? Debates to be had really.
01:43:11 Dr Katy Munro
Yeah, yeah. Have we covered all the treatments, Nick, or have I missed anything?
01:43:17 Dr Nick Silver
Well, you have missed some actually. You’ve missed the one that I thought you’d probably put highest on the list, which is psilocybin and LSD.
01:43:23 Dr Katy Munro
Oh yes. I think of those as kind of the dodgy ones. Yeah. I did want to ask you about those.
01:43:30 Dr Nick Silver
Dodgy ones?
01:43:31 Dr Katy Munro
The slightly less mainstream sources.
01:43:36 Dr Nick Silver
Yeah, slightly less. I would just like the disclaimer to say that I haven’t used LSD or psilocybin in this context or otherwise.
01:43:50 Dr Katy Munro
I have read things and had messages about magic mushrooms and obviously these are things currently illegal in the UK which also has a problem making them difficult to study. And there’s also something about very, very high dose vitamin D that I’ve come across, so.
01:44:09 Dr Nick Silver
Let’s do those separately, because vitamin D isn’t class A.
01:44:13 Dr Katy Munro
Yeah, exactly.
01:44:13 Dr Nick Silver
OK. Just to put the vitamin Ds, the Red Bulls, all those things. I think they’re internet social media fads that don’t actually relate to any good evidence from the sort of evidence that we would want to see as clinicians before we use things. If people want to go and try them, fine. But caffeine is going to cause other problems. It’s going to make your sleep quality worse. It’s going to have effects on mood. There’s a lot else going on there, so I would be avoiding caffeine and the Red Bulls and the vitamin. The vitamin D is not going to do any harm, fine to take vitamin D if you want to take it, but I don’t think it really helps.
01:44:56 Dr Katy Munro
Yeah, it’s the taurine as well that that people mention, the taurine in Monster drinks and I know generally the taurine is in the high-caffeine drink so you don’t get one without the other.
01:45:07 Dr Nick Silver
Yeah, so taurine is very similar to caffeine. It’s another stimulant and I don’t think there’s any good evidence that these things actually have a role to play in cluster headache, but if it’s something that patients want to go and try, they can try it. But they just need to be aware of the problems that arise from having a lot of caffeine, you’re going to get a lot of rebound and background headaches, fatigue. Caffeine destroys sleep for up to a week after having it. It’s not about just the few hours afterwards. And taurine will do the same, so I personally don’t advocate that. I think we’ve got far better proven effective acute treatments than that. Patients should be coming to us. They should be having their triptans. They should be getting their oxygen. Maybe their gammaCore. That’s where I would go for the majority of patients.
So coming on to the more dodgy ones, the class A drugs. Obviously we can’t advocate these, but we do get stories back and we hear, you know, patients very kindly will tell us what they have tried and what’s happened. I think that the magic mushrooms is probably — if you’re going to do something in terms of safety, the magic mushrooms would be safer than the LSD because the magic mushrooms are microdosing and they’re using tiny bits of that on a daily basis.
And I’ve seen a few people who can switch their bouts off reliably, microdosing magic mushrooms. So, you know, if you lived in a country where they were legal, I think that would be a reasonable thing for you to try. But bear in mind that they’re not. They’ve not gone through any licencing. They’ve not gone through any safety criteria. There are potential psychological impacts of magic mushrooms, but maybe not so much with microdosing. I think microdosing is a reasonable compromise.
What would be nicer is to find out why psilocybin does this in magic mushrooms. And see if there’s a version that could be adapted from it that has the benefits without the psychedelic effects that could actually be marketed and go through clinical trials, and certainly as a trustee of OUCH UK, you know, I have actually raised as to whether we should be looking at trying to forward research in this area with psychedelics because they are a treatment target and we are aware, for instance, in places like King’s in London, they’re starting to look at psychedelics for treatment of refractory depression. You need a lot of psychological support to go through this. You need psychologists. It’s very hard to double-blind this because people need so much support in it. It’s hard, you know, to say you’ve had LSD or not-LSD. I think most people would know that it was a sugar-coated pill and not LSD, because they weren’t flying or doing other things.
01:47:49 Dr Katy Munro
Yeah.
01:47:50 Dr Nick Silver
And then the worry with LSD is the flashbacks. You can get acid flashbacks from LSD that can happen throughout your life and can be really quite disturbing. LSD is not a simple one, but I think if we were to do this, we need to do it in guided proper control studies where there’s full psychological support for the patients, where we actually, use the knowledge and the experience of the psychiatry teams that have done this for refractory depression so we have all the support on hand. We know what the potential risks are, and I think we have to come up to it in that in fashion rather than ad hoc.
I wouldn’t recommend anyone takes LSD for cluster headache. If someone wanted to try magic mushrooms, I wouldn’t recommend it, but I would say it’s up to them if they wanted to try, we would rather see that they’re using licensed treatments where we know the safety and also, they’re not going to end up in prison if they take it.
01:48:57 Dr Katy Munro
That’s pretty important really. And so going forward then, are there any promising things on the horizon that you think will, rather than researching things which are class A drugs? Are there any other new therapeutic interventions that you’re aware of that are coming up in studies?
01:49:15 Dr Nick Silver
I want to know what the gepants do for cluster headache and we’re using them for migraine. These are a number of new drugs, things like rimegepant, atogepant, ubregopant, there are a few of these that are coming out for migraine. And I’m sure, like everything else, they’ll be tried on trials in cluster headache at some stage or people will try them and see if they’ve anecdotally given benefit.
I’m not aware of any other sort of more specific treatments for cluster headache. I don’t know if you are, Katy, that you’ve thought about any?
01:49:50 Dr Katy Munro
No, I’m not. I think we need more but I’m not aware of any remarkably different things.
01:49:58 Dr Nick Silver
Yeah, I think we do need them, but I think with all these things, it’s the law of percentages, isn’t it? You try your first thing and, you know, if we look at what we’re doing with cluster headache as a preventative, I would say that 50 to 75 — take 100 people, 50 to 75 will be sorted out with nerve blocks. If we go to gammaCore 50% of the remaining ones will be sorted out with gammaCore. So we’re down to about 25-30 out of the original 100 who still need sorting out. If we then give them verapamil, about 70-80% of them will be sorted out with verapamil. So we’re down to about 10 people out of 100 where they’ve gone past three treatments and they’re not willing.
So I think there’s a lot of optimism there that we’ve actually got some really good things. Yeah, with your acute attack treatments, you know, I would suggest that 70% or more will respond to sumatriptan injectors or nasal sprays. So just getting the right things that we know of is a really good start. If we just get all the patients with cluster headache, the actual treatments that we know are there under the right specialists, then we’ve actually got a hugely improved situation in the UK. I think the biggest problem is that people aren’t accessing that care, they’re not accessing the right specialists. And I would urge anyone with cluster headache that’s been referred to ask to be seen in a specific designated headache, if there is one in your area, and if you’re not in one an area with that, then you can be referred to other places. For instance, you know, I’m sure in London, at Queen Square and Guy’s and Saint Thomas’s, they’ll take patients out of area. I know they do. They take patients out of area for referrals.
01:51:23 Dr Katy Munro
Yeah.
01:51:41 Dr Nick Silver
I know at the Walton Centre in Liverpool we take patients out of area all the time. The National Migraine Centre is a really good place to start if you really don’t know how to get into the system, and that’s a very easy thing to access. You know, there are a lot of things that people can do there to get into the system, but try and see the right person.
01:52:03 Dr Katy Munro
Yeah, we do prioritise if we hear that somebody is booked with us at the National Migraine Centre and they’ve indicated that they think they have cluster headache, we get them in as quick as we can. I mean, it’s a video consultation initially, but we can often write a report to their GP that will help them to get the basic stuff that you’ve mentioned and maybe the referral on that they might need. And I think luckily OUCH, the Organisation for the Understanding of Cluster Headache, and the National Migraine Centre have very strong connection and they send us a lot of patients, follow up on their queries or on their helpline or they’ve done the quiz on the website, which I think is really helpful as well.
01:52:45 Dr Nick Silver
Yeah, OUCH will also direct them to some of the specialist units as well.
01:52:52 Dr Katy Munro
Yes.
01:52:53 Dr Nick Silver
Just interestingly I was just going to say most of our headache consults since the pandemic have been video as well to start with. Obviously if they need examination or investigations or they’re going to need nerve blocks or whatever, we might do that ourselves or bring them into the nurse specialist service depending. But a lot of headache management can be done remotely. So you know, the idea of going to the Walton Centre for a headache consult is much easier than it used to be. We get referred quite a few patients from, you know, down as far as Plymouth or get quite a lot from London as second opinions. We get them from Ireland, Northern Ireland, Scotland. So you know a lot of patients will come, and if it’s video assessments, then you know, at least for that part of it, it can be done by video. If they need physical treatments like nerve blocks, obviously that’s a bit more tricky.
01:53:48 Dr Katy Munro
I was going to say, and I didn’t put this on my list of topics, but it popped into my head earlier on children and cluster headache. I sometimes have heard from patients saying, you know, my child is having these attacks. They sound very, very typical of cluster headache. But they have really battled even more, possibly, to get a diagnosis or treatment. And how common is it in children?
01:54:15 Dr Nick Silver
Yeah. So I think it’s a double-edged sword. I think it’s quite rare in children, but it is seen and I think it’s often misdiagnosed in children. And I’ve seen patients who are diagnosed as having behavioural disorders, smashing up their room at night. Every night they go to bed and they smash up their room. And that was cluster headache and I’ve seen patients with — well, I’ve seen a few patients now, but with sort of very severe learning difficulties where they’re thought to have behavioural disturbance. But actually when you look at them in the attacks, you’ve got clear autonomic disturbance. So I’ve seen that and I used to treat children at the Walton Centre who have been refractory, the Alder Hay Headache Clinic used to send them to me. So I used to see quite young children even, who had been seen by paediatricians.
I think it’s quite rare, but I also think it’s missed when it does come, because I just don’t think, it is not on their radar that the child’s going to be presenting with cluster headaches. And then we’ve hardly got any designated consultant paediatric neurologists who do headache as their main thing. Obviously there’s Doctor Prabhakar in London and Doctor Abu-Arafeh in Scotland, I think.
Yeah. So it’s a real shortage and I mean even paediatric neurology has imploded in this country. I think certainly in Alder Hay, I think we’re seeing they’ve lost quite a lot of their neurologists there. Headache was never done by the neurologist, it was always done by the general paediatricians. Actually the one good part of this is I think is we’re often, as neurologists, interacting more with the transitional clinics for things like epilepsy in our district general hospitals. And then that’s giving us a nice working relationship with paediatricians and we’re starting to discuss non-epilepsy things.
01:56:15 Dr Katy Munro
Yeah.
01:56:16 Dr Nick Silver
And transition and then getting a bit more of a connection there. I’m certainly finding that locally where I work, as I do transition epilepsy clinics. And it’s quite nice actually seeing some of the paediatricians and what they’re doing and I think some of the general paediatricians are doing a fantastic job out there for headache and others just don’t really know very much about it. So I think there’s an advertising campaign that’s needed there.
01:56:39 Dr Katy Munro
Thank you very much. Nick, I think what I’d like to do is come back another day and do an episode on hemicrania continua and the TACs because we haven’t really touched on those. But this has been a really full and really interesting complete episode on cluster headache and all the treatments and issues around it. So thank you very much for today and we shall meet again to do another recording.
01:57:06 Dr Nick Silver
Oh, it’s an absolute pleasure, Katy. Thank you for asking me.
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This transcript is based on a past episode of the Heads Up podcast and reflects information available at the time of broadcast – some facts may have changed or new treatments become available since.
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