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June 8, 2001 -- Walking down a street in Honolulu, Mark Moyad, MPH, an expert in nutritional supplements for sexual disorders, was stopped by a merchant who asked him if he'd like to buy some "Viagra."
Intrigued, Moyad followed the man into the store. As it turns out, the merchant was not selling Viagra, but an herbal supplement called "Vigra" with an asking price of $75. Upon inspection, the product was found to contain a host of compounds touted -- but never proven -- to improve sexual functioning: ginseng, zinc, L-arginine, and saw palmetto, among others.
Moyad and others at a meeting of the Sexual Medicine Society of North America say this episode on the streets of Honolulu illustrates the enormous and lucrative market for herbal supplements to treat erectile dysfunction and other sexual disorders. The Society met this week in Anaheim, Calif., in conjunction with the American Urological Association.
"In my opinion, this is the largest profit area of the [herbal supplements] industry," Moyad says. "They may not be the hottest selling supplements out there, but the average cost runs $50-100 per bottle."
Moyad, who is completing his medical degree at the University of Michigan School of Medicine, is affiliated with the complementary/preventive medicine in urology and oncology there.
And most of these products have a long way to go before they are proven to live up to their claims. "Most erectile dysfunction supplements have a very slow response, if any," Moyad says. "This area begs for more research and objectivity."
The compounds found in Moyad's bottle of Vigra are among the usual suspects in compounds sold over the counter to promote sexual health. Another popular one is the steroid dehydroepiandrosterone, or DHEA, Moyad says.
Yet scientific studies to test the claims of these compounds are invariably weak. In almost every case, the claims are based on studies that did not compare the supplement against another drug or a placebo, were not long enough to determine long-term effects, or showed significant side effects, Moyad says.
Despite this, supplements for sexual disorders, including erectile dysfunction, abound, and the Internet is a popular, confidential venue to advertise and sell them.
"The web is probably a good place for some men to seek information about erectile dysfunction," said James H. Barada, MD. "Erectile dysfunction is an intensely personal issue, and many men feel more comfortable pursuing information in utmost confidentiality. Unfortunately, the Internet can be a very dark place because it provides confidentiality without control of content."
Barada says that more than 50,000 web sites specialize in herbal medications, and "a significant number of these sites also provide products for sexual dysfunction." Barada is with the Center for Male Sexual Health in Albany, N.Y.
In an informal study at his clinic, Barada asked six men with sexual disorders, including erectile dysfunction, to spend two hours on the web searching for products to treat the disorders. The men were able to find 16-39 different nonprescription medications, claiming to treat erectile dysfunction or premature ejaculation or to increase libido and general sexual stamina, Barada says.
Independently, Barada says he was able to find nearly 175 different sites and 75 products using the following search words: "better than Viagra," "safer than Viagra," or "faster than Viagra."
"When we looked at some of the specific products, they were multiple compounds of undetermined efficacy for treatment of erectile dysfunction," Barada says.
And many sites claim their products are "FDA approved," but a reading of the fine print reveals the approval has been for purity only, not for treatment of a disorder, Barada says.
David Schardt, PhD, of the Center for Science in the Public Interest, says the marketing of supplements was boosted by the passage of the Dietary Supplement Health and Education Act of 1994. That legislation gives manufacturers the freedom to market products with little proof that they live up to their claims, he says.
"You don't have to have any evidence that the substance you are marketing has any efficacy or even any biological effect," Schardt says. "It could be totally inert, or you could have evidence that it doesn't work and still sell it as a dietary supplement."
Schardt explains that the 1994 law provides two tiers for regulating claims made on supplement packages. One tier regulates claims made about a product's ability to prevent, treat, or cure disease. The criteria for making those claims are extraordinarily strict, and no herbal product is likely to pass the grade any time soon, Schardt says,
"None of the dietary supplements being sold for sexual dysfunction have anywhere near the evidence required by the FDA for the approval of a health claim," Schardt says. "It is unlikely you will see any dietary supplement being able to make a claim that it has any effect on prevention, treatment, or cure of any sexual dysfunction."
But the second tier of the law's regulation addresses "structure-function" claims. These are claims that a product affects the structure or function of the body -- and these criteria, much less stringent, are where herbal product manufacturers have considerable leeway. For instance, ginseng can be touted as "improving sexual well-being" under the regulation, Schardt says.
Moyad will be chairing a committee of the Society for Sexual Medicine to look at all the data on herbal supplements and to make recommendations to physicians for their patients. "It is time for researchers and physicians to get involved and look at the data objectively," Moyad says.