Once a prescription drug is approved for at least one indication, physicians are free to prescribe it for any other disorders or symptoms for which they believe it would be effective, a practice called off-label prescribing. Now some doctors are prescribing sildenafil (Viagra) off-label for women with sexual dysfunction.
Sexual dysfunction is common for women taking selective serotonin reuptake inhibitor (SSRI) antidepressants, encompassing decreased interest in sex and physical arousal, painful intercourse, and difficulty reaching orgasm.
That's why many women stop taking SSRIs, but a new study suggests that the erectile dysfunction drug sildenafil (Viagra) can help. The study was reported in the Journal of the American Medical Association (Volume 300, page 395).
Researchers enrolled 98 women treated with SSRIs for major depression, average age 37, who were experiencing sexual dysfunction. Half were randomized to take 50 to 100 mg of Viagra one to two hours before sexual activity; the others were given a placebo. The participants' sexual function was measured using standard questionnaires.
After eight weeks, nearly three out of four women experienced better sexual response. Only 28% of women taking Viagra reported no improvement in sexual interest and satisfaction compared with 73%of placebo takers. The most common side effects were headaches, flushing, and indigestion -- but no women dropped out of the trial because of these.
In men, Viagra inhibits an enzyme that results in improved blood flow to the penis, and it appears that the same enzyme is in female genital tissue. Viagra is not yet approved for women, but doctors may start prescribing it for this purpose.
