Botox for Migraine


What is BOTOX®?

BOTOX ® is a brand of botulinum toxin.  Some people use the word to mean any form of botulinum toxin but this can lead to misunderstanding.  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.


It’s not just 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.  This has been proven and the FDA approved this for chronic migraine.   It is also used to treat other illnesses including hemifacial spasm, cervical dystonia, and limb spasticity.


Can it be used for migraine?

BOTOX  is only for chronic migraine, not any other sort of 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 migraine  features, such as nausea, light or noise sensitivity, pulsating or lateralized 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 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, although each patient is different.  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:

  • Have had problems with injections (eg. fainting) in the past
  • Have had problems with previous botulinum toxin injections
  • Have inflammation, weakness or wasting of the muscles/skin where your doctor plans to inject
  • 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
  • Suffer from any other muscle problems or chronic diseases affecting your muscles
  • Suffer from certain diseases affecting your nervous system
  • Have an eye disease called closed-angle glaucoma or were told you were at risk of developing this type of glaucoma
  • Have had any surgery that may have changed the muscle that is being injected
  • Will have an operation soon
  • Are taking any blood thinning medicine

What side effects might I get?

The injections are slightly prickly or stingy. It is possible, though rare, to have an acute allergic response minutes after the first set of injections.

Less than one in ten patients experience each of the following side effects:

  • Worsening migraine. This can begin within a day or two of the injections, usually lasts a small number of days.
  • Rash, itching
  • As with all injections; pain, bruising, bleeding or infection where the injection was given are a possibility
  • Drooping of eyebrows or eye lids. This begins after a couple or a few weeks and can last for a small number of weeks.
  • Muscle weakness, pain, cramp, stiffness or tightness
  • Weakness and pain in the neck. This begins after a couple or a few weeks and can last for a small number of weeks.

Less than 1 in 100 may experience:

  • Difficulty in swallowing
  • Skin pain
  • Jaw pain
  • Swollen eyelid