(WASHINGTON) -- Botox, a drug famous for smoothing out wrinkles, could make life a little easier for people with urinary incontinence. By paralyzing the muscular lining of the bladder, the drug decreases the urgency and frequency of urination.
Botox maker Allergan has applied for Food and Drug Administration approval in people with multiple sclerosis and spinal cord injury whose conditions result in bladder overactivity.
"Those people are very much affected by this," said Caroline Van Hove, Allergan's vice president of corporate affairs. "The conditions make the bladder muscle involuntarily contract, and that causes patients to have to go to the bathroom frequently and unexpectedly."
Approval could come by the end of the year, potentially making urinary incontinence the eighth condition treated with Botox. Only one use is cosmetic; the other conditions include chronic migraine and spasticity.
"The uses of Botox are increasing," said Van Hove, adding that medical indications currently account for roughly half of the drug's $1.4 billion in worldwide sales, the remainder coming from cosmetic uses. "With the new uses, definitely that 50-50 split will sway more towards therapeutic."
There are other drugs that perform multiple roles, including a skin cancer cream used to smooth out your facial wrinkles, a baldness drug to protect against prostate cancer, and a drug for enlarged prostate and possibly prostate cancer that may stop baldness.
Once a drug has been approved for one use, doctors can prescribe it "off-label" when it is shown to be useful for something else. And an increasing number of drugs are prescribed in this manner. Off-label use of medicines accounts for about one fifth of all prescriptions, according to a 2008 study in the New England Journal of Medicine.
Many of these off-label uses meet with controversy and questions about their value, particularly since the FDA has not yet approved them. (As a result, drug companies cannot advertise off-label uses.) But in other cases, the alternative uses are well-known in the medical community -- though perhaps not among the general public -- and are regularly exploited.
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