The bacterium Clostridium botulinum produces a class of proteins known as botulinum toxins. The seven varieties of Botulinum Toxins now known are A, B, C1, D, E, F, and G. Injection forms of three of these are readily available for clinical usage in the US. These fall into two categories: type A, which includes the Allergan, Inc. products Botox, Dysport, and Xeomin, as well as type B. (Myobloc, produced by Solstice Neurosciences, Inc).
Injections of Botulinum Toxins are used to treat particular varieties of dystonia. Involuntary muscular contractions of opposing muscles that can lead to twisting and repetitive motions or aberrant postures are the hallmark of the neurologic syndrome known as dystonia. The FDA has approved the use of botulinum toxin injections for the management of cervical dystonia and blepharospasm.
