The world's most deadly neurotoxin, approved only last year to eliminate frown lines, is captivating medical researchers around the world. Botox, they say, may be able to treat migraines, drooling, incontinence, obesity and -- now also getting a lot of attention -- body odor.
"There is a lot of hype around the cosmetic use, but that is really the tip of the iceberg," said Dr. Andrew Blitzer, a New York City otolaryngologist who has treated patients with the toxin for two decades. "It's being used for so many other things. People are looking at toxin use for anything involving [acetylcholine] release."
It's the acetylcholine release that is the trigger of underarm sweating and, therefore, body odor.
A study published last week in Archives of Dermatology showed that injections of botulinum toxin A in the armpits dramatically reduced body odor in healthy young men and women.
The work follows an earlier study showing that Botox can reduce sweating for several months.
Allergan Inc., which makes Botox, says it plans to ask the Food and Drug Administration later this year for approval to market Botox for hyperhidrosis, the medical term for severe sweating.
Because some people with hyperhidrosis resort to surgery on the armpit nerves to reduce sweating, Botox is a welcome alternative, doctors said.
"The significant demand for Botox for hyperhidrosis of the armpit has surprised me," said Dr. Arnold Klein, a professor of dermatology at the David Geffen School of Medicine at UCLA. "The patients are incredibly grateful individuals. They have a history of spoiling expensive clothes, being embarrassed or, at an extreme, are so plagued by the problem they won't even date."
But the injections are also sought after to combat normal sweating. Dr. Leslie Baumann, a Miami dermatologist, says Botox is increasingly popular in sticky South Florida. She has given armpit Botox injections to teenagers who are self-conscious about sweating and even injects Botox in the palms of athletes who want a better (drier) grip on a baseball or basketball. The cost of armpit injections is about $500 in most doctors' offices.
The toxin stops sweating by preventing the release of acetylcholine, a substance that causes muscles to contract and nerves to induce sweating.
Control of sweating is only one blip on the Botox radar screen, however. Allergan is also exploring additional uses of the drug for controlling migraine headaches and for adult spasticity, which is typically caused by a stroke and can include such things as a clenched fist or uncontrollable limb movements.
The toxin was first used for neuromuscular disorders, such as uncontrolled blinking, crossed eyes and cervical dystonia, which causes neck contractions. It was during that research when doctors noted that facial injections smoothed frown lines.
Toxin can limit movement
Blitzer believes that Botox might help people who drool by blocking the salivary glands. Other researchers are testing the toxin on sphincter problems, including bladder control problems, anal fissures and esophageal sphincter problems that involve difficulty swallowing.
Other researchers are testing the toxin in areas of the body where physicians would like to limit movement to facilitate healing.
For instance, said Blitzer, injuries to the larynx might heal more quickly if Botox is used to temporarily paralyze function. Even some bone fractures might heal faster if the muscles attached to the bone are temporarily paralyzed.
Still other studies are targeting the toxin's potential to help people with facial paralysis resulting from surgery or a condition called Bell's palsy. It also might help control chronic runny nose and improve the pain associated with temporomandibular joint syndrome, which is poor function of the lower jaw.
A gastroenterologist in Texas has even launched a small study to see if Botox injected into the stomach might weaken the stomach muscles and reduce contractions enough to make obese people feel full and reduce their food intake, Blitzer said.
The enthusiasm for the toxin is fueled, in part, because it has proved safe, he said. "It has now been used worldwide in thousands and thousands of patients. And there are few side effects if the doses are small."
Other types of botulinum toxin besides the type A strain are also being tested for various medical uses, said Baumann.