Apr 18, 2002 (CIDRAP News) The Food and Drug Administration (FDA) this week endorsed a widespread cosmetic procedure by approving the use of botulinum toxin type A to temporarily smooth frown lines between the eyebrows.
Botulinum toxin is a protein produced by Clostridium botulinum, the cause of botulism, one of the six diseases considered most likely to be spread by bioterrorists. Allergan, Inc., Irvine, Calif., sells botulinum toxin type A as Botox Cosmetic.
In medical use, small doses of purified botulinum toxin are injected into muscles to block the release of acetylcholine from motor neurons, thereby preventing muscle contraction, according to the FDA. The toxin thus weakens or paralyzes the injected muscle.
Allergan said in a news release that the FDA approval is for use of the toxin to smooth vertical lines between the eyebrows (glabellar lines) in adults up to the age of 65. Botox was first approved in 1989 to treat two eye-muscle disorders, blepharospasm (uncontrollable blinking) and strabismus (crossed eyes), the FDA said. In December 2000 the FDA approved Botox for treating cervical dystonia, a disorder that causes severe neck and shoulder muscle contractions.
The FDA approval was based on placebo-controlled, randomized clinical trials involving a total of 405 patients with moderate to severe glabellar lines who were treated with Botox. "After 30 days, the great majority of investigators and patients rated frown lines as improved or nonexistent," while few patients in the placebo group showed improvement, the FDA announcement said. The improvement lasted up to 120 days. The FDA recommended that Botox be used no more than once every 3 months.
Botox injections are the fastest growing cosmetic treatment provided by surgeons in the United States, according to Roberta D. Sengelmann, MD, a Washington University dermatologist and otolaryngologist who was quoted in Allergan's news release.
Allergan officials said Botox therapy is used in 70 countries and is being investigated in the United States as a possible treatment for excessive sweating, post-stroke spasticity, back spasms, and headache.