Raloxifene, a selective estrogen receptor modulator, is used to treat and prevent osteoporosis in postmenopausal women. While this drug acts as an estrogen agonist in bone, it has estrogen antagonist effects on uterine and breast tissues. Although the effect on vaginal lubrication is unknown, reports of increased hot flushes suggest that raloxifene could adversely affect sexual functioning. Modugno and colleagues investigated the effect of raloxifene on sexual function in postmenopausal women.

They requested information from a subset of patients taking part in a large international study of more than 7,700 women assigned to receive raloxifene (60 or 120 mg daily) or placebo for treatment of osteoporosis. More than 900 women were asked to complete a questionnaire about sexuality at the baseline assessment and again after 36 months of treatment. The questionnaire was derived from the McCoy Sex Scale Questionnaire, and it assessed sexual activity and desire over the previous six months.

Questionnaires were completed by 651 women treated with raloxifene and 329 women who received placebo. In the raloxifene group, 58.2 percent were married, compared with 54.7 percent in the placebo group. In both groups, the mean age was 68 years, and the mean age at menopause was 48 years. The average body mass index was 25 kg per m² in both groups. At baseline, the levels of sexual activity were similar in each group (47.4 and 44.5 percent). The groups also reported similar desire for sexual activity (58.8 and 56.0 percent). At follow-up, 29.7 percent of women treated with raloxifene reported no change in sexual feelings and 34.1 percent reported improvement. In the placebo group, 26.6 percent reported no change and 37.2 percent reported improvement. Similarly, 30.8 percent of raloxifene-treated women reported no change in sexual problems and 38 percent reported improvement, whereas 29.1 percent in the placebo group reported no change, and 40 percent reported improvement.

The authors conclude that raloxifene therapy was not associated with a decrease in sexual function or desire in postmenopausal women.