Since the dawn of time, people have looked toward elixirs and potions to improve their sex lives. Why else, after all, would one consume ground tiger penis, horny goat weed and Spanish Fly?

Perhaps because nearly one in five men in the U.S. suffer from erectile dysfunction, according to a recent study in the American Journal of Medicine. Some researchers have estimated that as many as 40% of U.S. women have low libido or inability to reach orgasm. Most quick fixes simply don't work, and some, like Spanish Fly, a supposed aphrodisiac derived from beetles that can cause kidney damage, are harmful.

But modern medicine has found ways--both proven and experimental--to improve your sex life. One place to start: old-fashioned remedies, which some say work best. Regular exercise can actually improve erectile function in most men, says Andrew McCullough, a urologist at New York University Medical Center--and we're talking jogging, not the acrobatic feats found in the back of a magazine. Not particularly athletic? Therapists say that paying attention to your feelings is as important as any pill, nose spray or cream.

"Have a really wonderful role-play with your partner, have a really great dinner out or watch a romantic movie together," says Robert Dunlap, who has researched aphrodisiacs at the Institute for Advanced Study of Human Sexuality in San Francisco. "The greatest aphrodisiac is your mind."

Hope In A Bottle

But that's not stopping the $600 billion global pharmaceutical industry from trying to think up new sex drugs. Viagra, the little blue pill Pfizer launched a decade ago, brings in $1.7 billion in sales every year. Cialis, the longer-acting imitator made by Eli Lilly, rakes in another $1 billion, with several hundred million more for Levitra, from Bayer and Schering-Plough. Other remedies increase blood flow, like the penis injection Caverject, and bring in $30 million more.

A product that could improve women's sexual function might bring in even more money, if it were truly effective. So far, though, companies have been unsuccessful. Viagra failed in tests on women. Procter & Gamble tried to push a testosterone patch for female sexual dysfunction through the Food and Drug Administration (FDA) but in 2004 the agency balked, citing a lack of long-term safety data.

Now the idea of using testosterone as a sex-booster for women is being pushed by Lincolnshire, Ill.-based BioSante Pharmaceuticals, Inc. Its LibiGel is rubbed on the upper arm daily, delivering testosterone, which is thought to increase libido, to the bloodstream over time. The company just began late-stage trials, and, after discussions with the FDA, will start a big safety trial before submitting data to regulators in 2009.

Palatin Technologies, of Cranbury, N.J., is trying to get in on the game, developing a nose spray, called bremelanotide, to treat men and women with sexual dysfunction. Applied 10 to 15 minutes prior to sex, it travels through the central nervous system to increase blood flow in the penile or vaginal tissue. The company hopes to get FDA approval for men in 2009 and women around 2011. "On the female front, we've got a chance to be first to market," says CEO Carl Spana. "People wonder how many women will come in for treatment, but my gut tells me they will come in."

What Really Works
Right now, the treatment available for women with female sexual dysfunction that has been reviewed by the FDA is a handheld vacuum that can be used with a doctor's prescription to increase blood flow to the clitoris. Called Eros Therapy, it is made by NuGyn of Minnesota. Devices such as this go through fewer hurdles than drugs; the Eros device has been tested in several dozen people, compared with hundreds for a pill such as Viagra.

Joy Davidson, a Manhattan-based certified sex therapist, worries that all this technology may cause some people to ignore important cultural factors that can cause sexual dysfunction. "There are agendas here that are not health-based, they're profit-based," she says. "If you're not looking at these elements--the emotional, psychological and cultural--then giving somebody a so-called magic pill is not going to solve the problem."

Future Fixes
Meanwhile, drug researchers keep coming up with even more out-there approaches. For instance, a gene therapy, which seeks to fix erectile function by altering the DNA of cells in the penis, then injecting them back in to the patient. It should work for six months, according to inventor Arnold Melman, the researcher at New York's Albert Einstein College of Medicine. He has co-founded a tiny biotech, Ion Channel Innovations, to develop the product, which even he doesn't expect to reach the market before 2012. No gene therapy has ever been approved.

"People always say gene therapy doesn't work, but at one point it will," says Melman. "We think this is the one."