(FORTUNE Magazine) – Roughly 25% of men experience some hair loss by the time they reach 25, and the percentage goes up about ten points a decade. A third or more of women will also have thinning hair by middle age. The good news: A small army of researchers is testing revolutionary baldness-battling treatments that should be ready a few years from now. Until then, existing prescription drugs do a decent job of helping to preserve the strands you've got.

Assuming you find hair transplants as distasteful as we do, the best bet is Rogaine (minoxidil), Propecia (finasteride), or both. If you rub Rogaine (up to $45 a month) into the scalp twice a day, you have a 59% chance of stimulating some new growth after four months--but you've got to keep using the stuff to maintain the effects. Propecia (up to $58 a month), which comes in pill form, has been shown to stop hair loss in 83% of male patients tested between ages 18 and 41. It too must be taken forever, and it can't be taken by women of childbearing age because it causes birth defects.

Baldness is usually triggered by a combination of genetic and hormonal factors, so researchers are attacking on both fronts. Glaxo-SmithKline is testing a drug called Dutasteride that can block nearly 100% of dihydrotestosterone (DHT), a hormone byproduct that activates hair-loss genes. The drug could hit the market in two to five years. There's also stem-cell therapy, in which doctors harvest stem cells from healthy hair follicles, multiply them in a test tube, and inject them into the skin. Human testing is just getting underway. The ideal treatment would be to identify the gene-driven process that causes baldness and then neutralize it with a topical lotion or implant hair-friendly genes. If that works, the old joke--if you want to save your hair, get a box--may finally be obsolete.

--ALEX TAYLOR III