Botox has been approved as a preventive treatment for chronic migraine headache by UK drug regulators. It is not exactly clear why it may work in chronic migraines but it is thought that, as well as being a muscle relaxant, it may work to block pain signals. Injections are made in muscles of the forehead and neck. When this is effective, the treatment typically needs to be repeated every three to six months.
Botulinum toxin A (Botox®) may be beneficial in patients with intractable migraine headaches that fail to respond to conventional preventive medication. The injections are administered to the scalp and temple. They may reduce the frequency and severity of migraine attacks after 2-3 months of injections. Botox must be administered every 2-3 months to maintain their effectiveness. The most appropriate duration of prophylactic therapy has not been determined. In most patients who are receiving prophylaxis, therapy must be continued for at least 3-6 months. A Plastic surgeon’s (Dr. Guyuron) studies showed that migraine headaches are caused by nerves in the face, neck and/or scalp being irritated by overly tight muscles so by loosening up these muscles, the pain can be cured.