Herbal Impotence Pills Get Some Scientific Scrutiny

From the WebMD Archives

May 16, 2000 -- They used to be advertised on the backs of muscle magazines, but ever since the huge popularity of Viagra, makers of herbal supplements for impotence have been touting their products on TV, radio, and the Internet. Some have even given their products names somewhat reminiscent of Viagra, like BioVgA.

Few of these herbal products have been through the rigorous testing required of FDA-approved drugs. What's more, no federal agency enforces quality control over their ingredients. So consumers may not know exactly what they're buying -- whether a jar labeled "ginseng," for example, really has ginseng in it, or even whether ginseng is safe and effective.

Yet, across the herbal supplement industry, change is afoot. "In the past few years, this industry has been in a fishbowl," Mark Blumenthal, founder and executive director of the nonprofit American Botanical Council, tells WebMD. "We're not waiting for the FDA to regulate us. We're doing it ourselves."

A case in point: ArginMax, an herbal mix touted to improve sexual function in men, manufactured by The Daily Wellness Co. of Mountain View, Calif. It's one of a growing number of herbal products being tested in controlled scientific studies.

In Hawaii, Thomas Ito, MD, has conducted preliminary trials of ArginMax, which contains L-arginine, an ingredient that has been shown to trigger a buildup of nitric oxide in the bloodstream and thus expand blood vessels. Ginseng and ginkgo biloba also are in the mix.

"We feel these are critical ingredients ... chosen based on extensive research," Ito tells WebMD. "About 35 papers back up the ingredients." Ito has presented results of his research at regional meetings of the American Urological Association, and has submitted a paper for publication in the well-regarded professional journal Urology. Ito, a former assistant clinical professor of urology at the University of Hawaii School of Medicine, is now an industry consultant.

One of Ito's studies involved 48 men, each of whom received a capsule at his urology clinic daily for four weeks. Half received the herbal formulation; half received a sugar pill. No one, including Ito, knew who was getting the real thing, Ito says. "We chose capsules, so no one could smell or taste the differences," Ito tells WebMD.

Nearly 88% of the participants who got ArginMax reported achieving better erections, and 75% said they had an improved sex life overall. Even the placebo group said they had better sex: 18.75% reported improved erections, and 18% reported an overall better sex life during the study. All the patients were checked for blood pressure and appetite changes, but no side effects were detected, says Ito, who is conducting additional studies at a Veterans' Hospital in northern California.

For women having sexual problems, a similar ArginMax formulation is being tested, Mary Polan, MD, PhD, chairman of obstetrics and gynecology at Stanford University School of Medicine, tells WebMD. She presented results of her preliminary study of the product at an international meeting on female sexual dysfunction in Boston last fall.

Her trial involved 49 women either nearing or at menopause, all reporting sexual dysfunction. "Across the board, there was a significant increase in sexual satisfaction in the women on the drug compared to the control women," Polan says. Some 76% of the group on the ArginMax formulation reported improved sexual desire, while 72% had greater satisfaction in their sex lives, 64% had an improved sexual relationship with their partners, 60% had better clitoral sensation, and 52% had more frequent orgasms.

The placebo effect definitely came into play, as in the men's study, Polan tells WebMD. In one category, for example, "Thirty percent of women got better on the placebo. But 60% of women get better on the drug. So there's a significant difference."

Polan says she was encouraged by the results. "I take care of a lot of peri- and post-menopausal women, and probably the second biggest complaint is decreased or ineffective sexual functioning." Currently, there is no similar drug for women nearing menopause, although estrogen-replacement therapy is reported to improve sexual functioning in menopausal women. There have been no large-scale trials of Viagra involving women, Polan tells WebMD.

The women's compound contains L-arginine, ginseng, ginkgo biloba, and the herb damiana, which is supposed to promote the relaxed state of mind that is important for sexuality in women, Polan says. Vitamins and minerals also were added.

She intends to follow the women in her study to determine the compound's long-term effects, and hopes to launch a larger trial. But how does a Stanford professor become involved in testing an herbal supplement in the first place?

The theory behind the product made sense to her, she says. "I felt it was a group of people who understood you need to develop some data. It's a small start-up company, so we're not talking about mega trials, but there should be some critically evaluated information. ... And I think we've shown that."

As for supplements in general, "who knows what all this stuff out there does for people?" Polan says. "Of course, if you live in California, many people use nutritional supplements as their sole source of medication. ... I never know what to tell patients, so when I see medications that at least have data behind them, I feel more comfortable."

Buyer beware, says one of the country's top prostate cancer surgeons, William Catalona, MD, a urologist with Washington University School of Medicine in St. Louis. He has seen thousands of men facing sexual dysfunction.

And he's heard bad reviews of the herbals: "A lot of [patients] try these medications. And some feel they help a little bit, but most of the word I get would not suggest that they are effective. ... Patients ask, but I usually don't recommend them because [they] haven't been tested and approved by the FDA to show they are safe and effective."

While the theory about L-arginine "could conceivably work," says Catalona, "I'm not sure there's any practical evidence to show it really does this. ... Even though [Ito's] studies look positive, there's not absolute proof at this point. With Viagra, it's been through the FDA, so we know it's definitely effective. As for its safety, the safety guidelines are pretty good.

"What you see in some advertising for herbals [is] they jump all over the fact that Viagra is said to cause deaths," he adds. "So I have a lot of patients who [don't have heart disease] or anything else that would make Viagra dangerous to them, but their wives won't let them take it. ... So some people who are afraid of Viagra take these things."

Those who want to go the natural route sometimes turn to naturopathic physicians like Seattle-based Don Brown, ND, who tells WebMD, "L-arginine is pretty safe; there aren't a lot of concerns. Nitric oxide has a mild [blood vessel expanding] effect. We know it does that." Still, he says, "I would consider the research on L-arginine at this point to be very, very preliminary with regard to its effect on erectile dysfunction."

The problem is that dietary supplements are unregulated, Brown tells WebMD. "Mechanism of action becomes the way that it's promoted to the public, and yet there aren't any good clinical trials to back up their claims."

From the offices of the American Botanical Council, Blumenthal takes issue with that. "One of the biggest myths about the entire botanical/herbal medicine industry is that it is unregulated." Although these supplements are not regulated as drugs, he says, "any claims must be truthful and not misleading. They have to be backed by scientific evidence." The Federal Trade Commission recently obtained large financial settlements from two supplement companies whose advertising made unsubstantiated claims.

The FDA is expected to issue some new, more stringent regulations for the manufacturing of herbal supplements later this year. The quality control of supplement manufacturing will then be required to meet the same standards as that for foods -- "somebody that makes tomato paste or tomato sauce or apple juice," Blumenthal says.

His organization has been trying for seven years to push the supplement industry toward higher standards, by testing 500 commercial ginseng products. "We have done it by the book and done it very fair, tested everything twice to make sure everything is accurate, contacted the manufacturer once we found a negative finding, and gave the opportunity to rebut our claim or explain the situation," Blumenthal says.

"Many manufacturers have told us that either ... because they knew we were testing ginseng or because they got an adverse finding from us, that they totally overhauled their operation. Now, not only is their ginseng better, but everything else they produce has a higher degree of reliability of the quality because they learned a lesson from us on the ginseng.

"And we haven't even published anything yet. They saw it was inevitable. The handwriting was on the wall."

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