What is BOTOX®?
BOTOX ® is a brand of botulinum toxin. There are other brands, but these have not been proved helpful in any form of migraine or headache. Some people use the word to mean any form of botulinum toxin but this can lead to misunderstanding – just as not all vacuum cleaners are Hoovers. The toxin comes from a germ (a bacterium) called Clostridium botulinum. The way it is taken from the germ and prepared for clinical use varies between the different manufacturers, so different brands of botulinum toxin may work differently, and should not be interchangeable.
Isn’t it a treatment for wrinkles?
Botulinum toxin gets into nerve endings and stops the nerve being able to respond normally to an electrical nerve impulse. Whatever that nerve normally does, stops working. So when facial expression muscles are injected, facial wrinkles are reduced. It was noticed by chance many years ago that people having cosmetic botulinum toxin had fewer headaches. Recently this was proven to work for chronic migraine; it is also used to treat other illnesses including hemifacial spasm, dystonia, cerebral palsy, and stroke.
Can it be used for migraine?
BOTOX® is licensed for the treatment of chronic migraine, defined as 3 months of at least 15 days of headache a month, of which at least 8 days have migrainous features, such as nausea, light or noise sensitivity, pulsating or lateralised pain.
How does it work in migraine?
It is thought that botulinum toxin gets into the small nerves that carry pain from the head to the brain, known as C-fibres. This reduces the amount of chemicals released from the nerve ending and therefore interrupts the feedback pathway that perpetuates migraine and headache.
How is it given?
BOTOX ® is given as a series of 31 to 39 tiny (0.1 ml) injections under the skin or into the muscles in and around the head of the forehead, above the ears, and into the neck and shoulders. The injections are repeated every 12 weeks until the patient no longer has chronic migraine, or until it is clear that treatment is not working. Normally a response is seen after the first or second set of injections; only about one in ten people respond to a third set of injections if the first two sets fail.
How effective is it?
The goal is not to become completely free of headache or migraine; but to improve quality of life, and to convert migraine from chronic to episodic.
About one in four patients do not respond; one in four respond well to the first or second set of injections, and half need more than two sets of injections to get a good response. Studies show that 47% of patients had a 50% or greater reduction in the number of days with headache.
The biological effect of botulinum toxin on nerves takes several days or a few weeks to work. You should not expect chronic migraine to improve properly in less than 4 weeks. Some patients do not start to improve until after their second set of injections which is given 12 weeks after the first set of injections.
Who can’t have BOTOX for migraine?
BOTOX is only for chronic migraine: not any other sort of migraine.
People who are pregnant or breastfeeding may not have BOTOX.
If you have other neurological disease, for example Bell’s palsy, a neuropathy, or Myasthenia Gravis, the risks of BOTOX are increased.
If you have recently (within the last 3 months) had cosmetic botulinum toxin then the side effects could be increased.
Tell your doctor if you:
ā Have had problems with injections (eg. fainting) in the past
ā Have had problems with previous botulinum toxin injections
ā Have inflammation, weakness or wasting of the muscles/skin where your doctor plans to inject
ā Have had problems with swallowing or food or liquid accidentally going into your lungs, especially if you will be treated for persistent muscle spasms in the neck and shoulders
ā Suffer from any other muscle problems or chronic diseases affecting your muscles
ā Suffer from certain diseases affecting your nervous system
ā Have an eye disease called closed-angle glaucoma or were told you were at risk of developing this type of glaucoma
ā Have had any surgery that may have changed the muscle that is being injected
ā Will have an operation soon
ā Are taking any blood thinning medicine
What side effects might I get?
The injections are slightly prickly or stingy and take about 5 minutes to complete.
It is possible, though rare, to have an acute allergic response so you should stay in the clinic for several minutes after the first set of injections.
Less than one in ten patients experience each of the following side effects:-
ā Worsening migraine. This can begin within a day or two of the injections, usually lasts a small number of days. It can be treated with triptans and/or regular naproxen 250 mg or 375 mg three times daily after meals.
ā Rash, itching
ā As with all injections; pain, bruising, bleeding or infection where the injection was given are a possibility
1. Drooping of eyebrows or eye lids. This begins after a couple or a few weeks and can last for a small number of weeks.
2. Muscle weakness, pain, cramp, stiffness or tightness
3. Weakness and pain in the neck. This begins after a couple or a few weeks and can last for a small number of weeks. It can be treated with regular naproxen as in (1) above.
Less than 1 in 100 may experience:
ā Difficulty in swallowing
ā Skin pain
ā Jaw pain
ā Swollen eyelid
If you have any difficulty in breathing, swallowing or speaking after receiving Botox contact your GP immediately.
If you experience hives, swelling including the face or throat, wheezing, feeling faint and shortness of breath please also contact your GP immediately.
Side effects relating to the spread of Botox far away from the injection site have been reported very rarely. If you experience any untoward side effects that you feel could be as a result of Botox please see your GP or visit A&E and notify NMC.
This information is provided as a general guide only and is not a comprehensive overview of prescribing information. If you have any queries or concerns about your headaches or medications please discuss them with your GP or the doctor you see at the National Migraine Centre.