Use of sildenafil associated with improvement in antidepressant-related sexual dysfunction

Women with sexual dysfunction caused by the use of antidepressants experienced a reduction in adverse sexual effects with use of sildenafil, commonly known as the erectile dysfunction medication Viagra, according to a study in the 23/30 July issue of JAMA.

Treatment-related sexual dysfunction is a frequent adverse effect occurring with medication use and is a major influence for early discontinuation of antidepressant treatment, which can lead to treatment failure. Sexual dysfunction is recognised as being associated with selective and nonselective serotonin reuptake inhibitor (SRI) antidepressants, which are the most frequently prescribed medications for outpatients age 18 to 65 years and represent 90 percent of the 180 million antidepressant prescriptions filled in the United States, according to background information in the article.

'Antidepressant treatment - associated sexual dysfunction is estimated to occur in 30 percent to 70 percent of men and women treated for major depression with first- or second-generation agents, a principal reason for a 3-fold increased risk of nonadherence that approaches 70 percent in the first months of treatment and leads to increased relapse, recurrence, disability, and resource utilisation by affected patients,' the authors write. It is believed no randomised controlled trial has demonstrated an effective treatment for women experiencing sexual dysfunction associated with SRIs.

H. George Nurnberg, M.D., of the University of New Mexico School of Medicine, Albuquerque, N.M., and colleagues compared the efficacy of sildenafil against placebo for treatment of sexual dysfunction (such as orgasm delay or lack of arousal [lubrication]) associated with SRI treatment in 98 women (average age 37) with major depression in remission. The randomised controlled clinical trial was conducted between Sept. 2003 and Jan. 2007 at seven U.S. research centres. Participants were randomly assigned to take sildenafil (n = 49) or placebo (n = 49) at a flexible dose starting at 50 mg., adjustable to 100 mg., approximately one to two hours before anticipated sexual activity, for 8 weeks.

The researchers found that 73 percent of women taking placebo, compared with 28 percent of women taking sildenafil, reported no improvement with treatment. On a clinician-rated severity improvement scale, women in the sildenafil group showed greater improvement in sexual function than women in the placebo group.

Headache, flushing, and indigestion were reported frequently during treatment, but no patients withdrew because of serious adverse effects.

'These findings are important not only because women experience major depressive disorder at nearly double the rate of men and because they experience greater resulting sexual dysfunction than men but also because it establishes that selective phosphodiesterase type 5 inhibitors (such as sildenafil) are effective in both sexes for this purpose. By treating this bothersome treatment-associated adverse effect in patients who have been effectively treated for depression, but need to continue on their medication to avoid relapse or recurrence, patients can remain antidepressant-adherent, reduce the current high rates of premature medication discontinuation, and improve depression disease management outcomes,' the authors write.