Off-label use of sildenafil (Viagra) relieved sexual side effects of antidepressants for women in a recent clinical trial.
Those side effects included lack of arousal sensation or lubrication and orgasm delay. They commonly occur with both selective and nonselective serotonin reuptake inhibitors (SRI).
“Treatment-associated sexual dysfunction is a principal reason for a risk of nonadherence and leads to increased relapse, recurrence, disability, and resource utilization by affected patients,” the researchers wrote.
Previous studies of selective phosphodiesterase type 5 (PDE-5) inhibitors, such as sildenafil, have been limited to men, and the FDA has not approved these drugs for women.
This study, led by H. George Nurnberg, MD, professor of psychiatry at the University of New Mexico School of Medicine in Albuquerque, randomly divided 98 women into two equal groups. They were then assigned to take sildenafil or placebo an hour or two before anticipated sexual activity. Dosage was adjustable, ranging between 50 and 100 mg.
All participants were in remission from major depression but continuing on SRI therapy to avoid relapse or recurrence. With a median age of 37 years, they were premenopausal and had been sexually functioning before they started SRI treatment. But all had experienced persistent sexual dysfunction for at least a month before the trial began.
After eight weeks, the sildenafil group had a mean Clinical Global Impression score of 1.9 compared with 1.1 among the placebo group. Only 28% of the women taking sildenafil reported no improvement compared with 73% in the placebo arm. Headache, flushing, and dyspepsia were frequently reported, but they were not severe enough to cause any participant to quit the trial.
Findings appear in the Journal of the American Medical Association (2008;300:395-404).
“These findings are important not only because women experience major depression at nearly double the rate of men and because they experience greater resulting sexual dysfunction than men, but because they establish that selective PDE-5 inhibitors are effective in both sexes,” the authors concluded.