Will there ever be a 'Viagra' for women?
By Dulce Zamora
WebMD Weight Loss Clinic - Feature
Reviewed By Brunilda Nazario, MD
Six years after Viagra revolutionized sexual ability for men, many women are still hoping for their turn. To date, the FDA hasn't approved a product to boost female sex drive.
It's no small problem. A low sex drive is the most common sexual complaint made by women -- up to 30% to 40% of them, according to Sandra Lieblum, PhD, director for the Center for Sexual and Relationship Health at the Robert Wood Johnson Medical School in New Jersey.
The Search for a Cure
Throughout the ages, various potions and contraptions have pledged relief, but the discerning have wondered if the so-called remedies are truly love liniments, or merely snake oil.
Just because someone makes a claim about boosting female libido, it doesn't mean that it's true, says Beverly Whipple, PhD, RN, FAAN, vice president of the World Association for Sexology. "We have to make sure that the claim is being made on scientific evidence."
Yet, even if something appears to work in scientific research, there is the concern that just being part of a study to improve a women's sex drive might itself have a suggestive effect on libido; it's called a placebo effect.
"It has to do with women's expectancies and hope that any intervention will prove beneficial," says Lieblum, noting that anticipation can also change behavior. "Any woman who goes into a trial to improve libido is motivated to be more active."
The power of placebo is so strong that many health experts look only to double-blind, placebo-controlled trials to prove a product's effectiveness. In these studies, a group of subjects receive a real drug, while another set gets a dummy substance. Neither the researchers nor the participants know which the real medicine is.
Apply this criterion to the dozens of aphrodisiacs for women out there, and the number of suitable elixirs dwindles down to possibly one or two that work for some women. Even with the best of studies, expert opinion varies on what works best for female libido.
There is a consensus, however, on just how intricate female desire is. "Women's drive is so complex that biology is only one factor that drives sex drive," says Jean Koehler, PhD, a licensed family and marriage therapist in Louisville, Ky., and past president of the American Association of Sex Educators, Counselors, and Therapists.
Besides biology, the following factors can affect female libido:
- Quality of the relationship
- Attitudes of upbringing
- Support of peer group
- Quality of touch and sex
- Understanding of partners
- Use of medications
- Emotional well-being
Trouble with one or a combination of these factors can affect women's sex drive. Such loss of interest in sex is medically identified as hypoactive sexual desire disorder (HSDD).
There are some popular products that have either been designed or tested to treat HSDD.
Despite rumors and various advertising claims to the contrary, there isn't a female Viagra out there.
"We know that Viagra doesn't work in women," says Whipple.
"Women are not minimen," Whipple explains. "We are different than men in what we want, what we desire, what feels good to us, and we're also different at the biochemical level."
Female sexuality is, indeed, so much more complex than male sexuality that even after several scientific studies involving about 3,000 women, Viagra-maker Pfizer hasn't been able to come up with conclusive findings. Earlier this year, the company announced it was ending research of Viagra in women.
But this does not mean there isn't hope for some women. Research is ongoing on several other products for female libido.
Two large studies presented at scientific meetings this year show the testosterone patch Intrinsa, made by Procter & Gamble, can increase sexual activity in 50% to 70% of women.
The participants, though, only include a select group of women with HSDD.
"Every study we've done so far on the testosterone patches in the public domain is just involving women who have had their ovaries removed (surgically menopausal), and they're all estrogen-treated before we add the testosterone," says Jan Shifren, MD, director of the Vincent Obstetrics and Gynecology Service Menopause Program at the Massachusetts General Hospital in Boston, who is involved in testosterone studies. "So despite estrogen therapy, they still have decreased sexual desire."
Women who have had their ovaries removed are good candidates for testosterone therapy, since the ovaries are a major source of testosterone as well as estrogen, says Shifren. "In these women, it was like we were restoring levels back to what it would have been had they still had their ovaries."
Shifren and colleagues recently tested testosterone patches on women who underwent menopause naturally and were taking estrogen therapy. The results of that study are expected in the fall. In addition, a trial of testosterone on menopausal women, not on estrogen therapy, is about to begin.
If all goes well, and the FDA gives its approval, the testosterone patch could be available in one to two years.
Some women use testosterone products designed for men, but these products have not been tested in large studies in women, and could have 10 times more hormones than women need, says Mary Lake Polan, MD, PhD, MPH, professor and chair of ob-gyn at Stanford University School of Medicine in California.
Too much testosterone in women could have masculinizing effects, such as hoarseness or deepening of the voice, unnatural hair growth or loss, acne or oily skin, decreased breast size, increase in the size of female genitals, and irregular menstrual cycles.
Additionally, other forms of testosterone such as creams and gels do not have conclusive evidence that they work to boost women's libido.
There is one FDA-approved androgen (male hormone) on the market for women. Estratest is a combination of oral estrogen and testosterone.
Although the product is only approved to treat estrogen-resistant hot flashes, it has been used "off-label" by doctors and patients. Off-label use means physicians prescribe drugs for a purpose other than what they are approved for.
Estratest has not been approved to improve sexual desire in menopausal women, but double-blind trials have shown it can do the job, says Shifren. "The nice thing is that it is a pharmacy-grade product designed for women. So there are a lot of data on safety and efficacy."
The drawback is that the drug is a fixed dose of a combination of estrogen and androgen. Women who may not need estrogen for hot flashes may not want to use the product.
"Estratest would be a very appropriate therapy for surgically menopausal women who, after surgery, notice hot flashes and a decrease in [sexual] desire," says Shifren.
Leiblum points out that Estratest and other drugs, while useful for some women, are not cure-alls for libido. "None of these [drugs] are probably going to be useful on their own," she says. "They all need to be seen as a multifaceted approach to both assessment and intervention."
Like all estrogens, the hormone may increase the risk of heart attack, stroke, breast cancer, endometrial cancer, and blood clots in the lungs or legs. Androgens can increase risk of liver cancer, and cause masculinizing effects in women.
There is some evidence that the antidepressant drug, Wellbutrin, may be able to boost women's libido.
In a 12-week preliminary study of 66 women most of who were not menopausal, 39% reported being satisfied with their levels of sexual desire. Harry Croft, MD, a psychiatrist and sex therapist based in San Antonio, reported the results of the study at the 2000 American Psychiatric Association meeting.
Experts say they are not aware of any large studies on Wellbutrin and sexual desire. But they aren't surprised that the drug may have some effect on women's libido.
"What happens sometimes is that people's sex drive goes up, because their depression is treated," says Koehler, noting that depression is often accompanied by lower sex drive. "So it may not be the Wellbutrin itself [that works]; it might be the feeling of being less depressed that is causing the increased sex drive."
None of the women in Croft's study was depressed when the trial began, but all had trouble becoming aroused or having orgasms.
Sometimes, a change in antidepressant drugs may help boost libido. SSRI-type medications such as Prozac and Zoloft are known to interfere with sexual desire. If a person switches from SSRI-type antidepressants to Wellbutrin, there may be an increase in sexual desire, because the others may be diminishing it, says Carol Rinkleib Ellison, PhD, a psychologist and author of Women's Sexualities.
On the other hand, Ellison says Wellbutrin could have the opposite effect of dampening desire. "People are really individual in how they respond to these medications," she says.
With names like Lioness, Xzite, and Rekindle, dozens of nutritional supplements line drugstore shelves with promises to enhance women's libido. Some of them even have an eye-opening price tag to go with claims. The daily supplement Avlimil, for instance, costs $324-$360 for a one-year supply.
Do any of them work?
Whipple says she knows of only two dietary supplements for sexual dysfunction that have been studied in double-blind, placebo-controlled trials: ArginMax and Zestra. The ArginMax trial looked at the supplement's effect on sexual desire, while the Zestra study looked at its effect on sexual arousal (libido is intact, but the woman has trouble becoming or maintaining aroused).
ArginMax appeared to not only have a positive effect on women's libido, but also showed satisfaction with sex lives -- an important, but often ignored factor, says Whipple.
Polan was one of the researchers involved in the studies on ArginMax. She says the supplement is safe for women to try on their own, but she still recommends that they first check in with their physicians.
"You don't want to miss what a doctor may pick up," says Polan. "You want to make sure there is not some organic, or metabolic, or physical reason for [the lack of sexual desire]."
Plus, it is important to make sure that herbal ingredients don't negatively interact with any medications you may be taking, says Whipple. For example, ArginMax contains gingko, which can promote bleeding. It is not an ingredient that would mix well with blood thinners such as aspirin or Coumadin.
Leiblum further warns that the FDA doesn't regulate natural ingredients. "Women may be getting very high levels, or very low levels, or totally zero levels of these supposed herbs."
Instead of looking at herbal remedies for lost libido, she recommends taking self-inventory. "It's more important to try to figure out why you lost [your libido], instead of trying to find a quick fix."
Changes in lifestyle, attitude, and relationships may not be bought in drugstores, but experts say they hold keys to unlocking libido woes.
"For women, sex drive is critically dependent on being healthy and really feeling good about a relationship. There will never be anything that we'll be able to pull out of our medicine cabinet that will be more important than those two things," says Shifren.
Part of being physically and emotionally healthy is having a sensible dose of realism. It's normal to have low libido, says Ellison. In fact, she says it's unrealistic to expect to feel a burst of desire all the time, as shown on TV.
In real life, where people are in long-term, one-on-one relationships with jobs, commutes, and kids, she says sexual drive isn't always present.
Instead of looking for libido, Ellison recommends creating opportunities to make time together special. "Maybe what you need to look for is a way to be more interested in your partner," she says.
Taking part in enjoyable activities such as walking with a partner, listening to music, having a glass of wine, taking a bath, or reading a romance novel can also help put women in the mood for sex. These activities can help women shift into their "sex self" from their role as mother, wife, employer, or employee, says Ellison.
It would also help women to be more pleasure-oriented rather than goal-oriented with sex. "Right now we have women fitting into a male linear model of sexual response: desire, arousal, and orgasm. But women don't work that way," says Whipple. "Sometimes holding someone's hand and being held and kissed is all [women] want, and it feels good. So enjoy that. Enjoy what you enjoy."
Published July 26, 2004.
SOURCES: Sandra Lieblum, PhD, director, Center for Sexual and Relationship Health, Robert Wood Johnson Medical School, New Jersey. Beverly Whipple, PhD, RN, FAAN, vice president, World Association for Sexology. Jean Koehler, PhD, licensed family and marriage therapist, Louisville, Ky.; and past president, American Association of Sex Educators, Counselors, and Therapists. Jan Shifren, MD, director, Vincent Obstetrics and Gynecology Service Menopause Program, Massachusetts General Hospital, Boston. Mary Lake Polan, MD, PhD, MPH, professor and chair, ob-gyn, Stanford University School of Medicine. Carol Rinkleib Ellison, PhD, psychologist; and author, Women's Sexualities. The Journal of the American Medical Association: Feb. 10, 1999. WebMD Feature: "Why Women Lose Interest in Sex." WebMD Medical News: Viagra Improves Sex for Some Women." Yahoo! News: "P&G Female Sexual Desire Patch Effective in Trial." Procter & Gamble web site. MedlinePlus Drug Information. WebMD Medical News: "Drug Improves Women's Sexual Desire." ArginMax web site. Zestra for Women web site.
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