Onabotulinumtoxin A (BOTOX®) is FDA approved for the treatment of chronic migraines, spasticity and cervical dystonia in adults. It is a medicine that is injected into the affected muscle(s). BOTOX® is the most common neurotoxin derived from the toxin Clostridium botulinum, the same bacterium that causes food poisoning. While this bacterium may be fatal in large doses, in small, medically regulated doses, it has been found to be an effective therapeutic tool in relieving chronic pain.
In regards to chronic migraine headaches, eligible patients must have 15 or more days each month with headache, lasting 4 or more hours each day. BOTOX has been studied to reduce headache days every month, preventing up to 9 headache days a month (PREEMPT trial).
The positive effects of BOTOX injections may be felt for several months, but they are not permanent. When these injections are helpful, it is usually recommended that they be repeated every 3 or 4 months for continual relief of symptoms. Physical therapy is often recommended after injections to restore flexibility and muscle function.