Botulinum toxin Type A (Botox) is produced by a bacterium called Clostridium Botulinum. The toxin, which blocks neuromuscular transmission, has been used for medicinal purposes. When injected in small quantities, Botox causes selective weakening and paralysis of muscles, thereby alleviating spasm and pain. To our knowledge, the drug has been approved only for certain problems involving the small muscles of the eyes. Doctors have used this for many other conditions, however; one of which is for the pain of a muscular condition called Myofascial Pain Syndrome, or Fibromyalgia.
The technique is being promoted over the internet and in the news media as a new "miracle cure" for fibromyalgia. Muscle pain is one of the features of fibromyalgia, but there are many other symptoms of fibromyalgia, which are not helped by Botox.
When injections are administered, it takes up to eight days before experiencing any relief of symptoms. Most relief is experienced at three weeks and injections are sometimes repeated every three or four months. Too frequent injections can lead to immunity.
Too frequent injections, depending on the location, can lead to weakness in the muscle.
The drug is expensive, costing up to $400 per injection.
The treatment is best administered by a trained pain management specialist at a pain clinic. It probably does have some beneficial effects in the proper clinical setting and relief can last up to about four months. I have had no personal experience with this technique.