Abstract

Botulinum toxin, the most potent biological toxin known to man, was first isolated in 1897. For 2 deca- des, botulinum toxin A has been used for treating various disorders associated with muscular hypertrophy. Current research efforts focus on new areas of application for botulinum toxin A in specific pain therapy, particularly in headache. Clinical data and experience to date have demonstrated that BTX-A is an effec- tive and well-tolerated therapy for various headache disorders. Its long-term action lasting several months obviates the need to remember to take medication several times a day. Although inhibition of neuromus- cular activity may alleviate a portion of the pain associated with headache disorders, it does not fully explain the pain-relief mechanisms mediated by BTX-A. A reduction in afferent sensory activity coming from pericranial and cervical muscles, and inhibition of peripheral and central trigeminal sensitization, may be the potential mechanisms by which BTX-A exerts its therapeutic effect in various headache disor- ders. Further investigations will define the accurate pathophysiologic mechanisms of BTX-A in the head- ache management. Korean Journal of Headache 6(1):54-69, 2005