Botulinum toxin has been approved by the Federal Drug Administration for treatment of chronic migraine. Botulinum toxin does not cure chronic migraine and it may not be effective in some patients. There have, however, been no serious injuries or deaths resulting from its use for this indication.

The administration of botulinum toxin is accomplished by injecting a small amount of toxin into the muscles of the head and neck. Dosage must be titrated for each individual. Any benefits resulting from botulinum toxin tend to wear off after about 3 months with a repeat injection required if benefit is to be maintained. Injections are usually done every 3 to 4 months with maximal effect peak achieved by about 2-3 weeks. Botulinum toxin is expensive and you should besure of what costs you will incur resulting from the injection.

The side effects of botulinum toxin used for chronic migraine may include:

• Temporary, and usually mild, facial weakness with facial injectionsTemporary, and usually mild, head or neck weakness with head/neck injections
• Reduction or loss of forehead facial animation due to forehead muscle weakness
• Eyelid drooping (ptosis)
• Temporary pain at the site of the injection or ecchymosis (black and blue mark) at the site of injection
• Temporary dry eye
• Temporary double vision
• It is also possible that as with any injection, there may be an allergic reaction or no effect from the medication.
• Reduced effectiveness after repeated injections is sometimes seen and rarely infection at the injection site may occur.
• There is the possibility of potential unknown risks associated with this treatment.

  Care will be taken to prevent these side effects. If therapy is given over a long time, atrophy and wasting in the muscle injected may occur.