Sexual Health: Revving Up Women's Sex Drive (cont.)
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.