In 2004, the U.S. Food & Drug Administration (FDA) approved BOTOX (onabotulinumtoxinA) for the treatment of severe primary axillary hyperhidrosis (excessive sweating of the underarms) in patients unable to obtain relief using antiperspirants.
OnabotulinumtoxinA is a natural, purified protein with the ability to temporarily block the secretion of the chemical that is responsible for “turning on” the body’s sweat glands. By blocking, or interrupting, this chemical messenger, botulinum toxin “turns off” sweating at the area where it has been injected. Botox injections are very shallow, meaning that the medicine is injected just below the surface of the skin, where it remains.
When used to treat underarm excessive sweating, Botox has been shown to result in an 82-87% decrease in sweating. Results start to be noticeable approximately 2 to 4 days after treatment with the full effects usually noted within 2 weeks. Dryness typically lasts 4 to 12 months, but some studies have found it can last as long as 14 months.