Human growth hormone was intended for children with growth disorders, but older people seeking the fountain of youth and athletes wanting a boost started finding illegal suppliers of HGH for muscle growth and overall toning.

The latest development involves Lumigan, a drug Allergan produced to treat glaucoma. The disease can lead to blindness if left untreated. The medication decreases pressure within the eye either by slowing the production of a fluid in the eye or by increasing fluid drainage. One of the side effects of Lumigan is longer, thicker and darker eyelashes.

Allergan developed a spinoff called Latisse, which the FDA approved for eyelash enhancement in December. Lumigan drops are used in the eyes; Latisse is applied to the upper eyelid. Bimatoprost is the active ingredient common to both drugs.

"Forget about fake lashes, they end up on your cheeks," says Liz Weber of Washington, D.C. "This is my favorite stuff ever."

Weber, 52, was distressed about having short lashes and bald spots, a condition called hypotrichosis. Her dermatologist told her the condition can be persistent after menopause. Weber had used fake eyelashes and was ready to try eyelash extenders when she found out about Latisse.

"Now, my daughter calls them my Bambi lashes," she says.

Dermatologists say customers are lining up. Richard Glogau, a member of the American Academy of Dermatology who practices in San Francisco, says he got his first shipment of 60 boxes three weeks ago and was sold out within a week. A box is a month's supply.

"I had no idea how big eyelashes were with women until this came along," Glogau says. "The response has been impressive. I was a little taken aback at first, but they report that their eyelashes got thinner as they got older or they were too blond."

One of the warnings for both Lumigan and Latisse is possible change in pigmentation of the eyelid and darkening of the iris. Though not harmful, once change of the iris does occur, it is permanent.

Weber's dermatologist, Marilyn Berzin of Dcdermdocs in Washington, D.C., says she believes Latisse is safe and is not likely to alter the iris color because it's not applied directly to the eyes.

Still, Andrew Iwach, a glaucoma specialist and spokesman for the American Academy of Ophthalmology, cautions people who have eye inflammation, glaucoma or macular edema to consult with their eye doctor before using Latisse.

It costs about $4 a day, and insurance doesn't cover it. Berzin says that after 16 weeks of daily application, it is possible to cut back to once or twice a week for maintenance of the lashes. If you discontinue use altogether, eyelashes return to their previous appearance.

David Pyott, chairman of the board and CEO of Allergan, expects Latisse to ultimately equal the cosmetic use of Botox. "Botox is for an aging population," he says. "Latisse can benefit anyone," including cancer patients who have had chemotherapy and lost their lashes. Their lashes eventually will grow back without Latisse.

The FDA did not approve Latisse for people under 18 or for pregnant or lactating women.