Efficacy of Botulinum Toxin Stereotype A and Its Relevant Mechanisms of Action in Both Cosmetic and Therapeutic Uses

Onabotulinumtoxin A (Botox®) is a parasympathetic autonomic blocking agent which acts as an inhibitor of the neuromuscular transmitter acetylcholine release and as a neuromuscular blocking agent, thereby inducing relaxation of selected muscle fibers for a duration of up to approximately 3 months duration. First approved by the FDA in 1989 and approved for further applications since 1991, the drug has now gained wide acceptance in cosmetic and other therapeutic applications, where the autonomic neurotransmitter acetylcholine blockade can bring about favorable cosmetic responses, particularly in the field of dermatology and cosmetic medicine. Since the original application of Onabotulinumtoxin A was approved for clinical use as a cosmetic agent, numerous additional applications have been approved by the FDA, all of which involve acetylcholine-mediated neuromuscular actions.