The basic science of botulinum toxin.

Understanding the basic science of botulinum toxin should serve as a fundamental first step for clinical therapy. This article endeavors to cover many aspects of basic research that also have clinical import. The two principal toxins of the clostridial family, Clostridium tetani and C botulinum, are described in detail. The five clinical manifestations of botulism poisoning are also outlined, and structural aspects and the mechanism of action of botulinum toxin are then presented. Finally, the immunologic and pharmacologic principles that define the various serotypes of botulinum toxin are set forth.