FDA approval of Addyi (flibanserin), or the “little pink pill,” was big news last year. It was applauded by some women’s groups as, finally, a first step toward addressing sexual dysfunction in women.
The FDA passed the drug by an 18-6 vote, after four clinical trials of 3099, mostly white, women for treatment of hypoactive sexual desire disorder, or HSDD. The women tested were aged 18-56 years old.
“Those who took flibanserin reported a modest but measurable rise in sexual desire and increased their number of 'sexually satisfying encounters' by roughly one per month,” wrote the Los Angeles Times.
Now one year later, a new study by Netherlands researchers shows that those results may be overestimated.
Researchers reviewed eight clinical trials, five published and three unpublished, and found that use of Addyi only resulted in one-half additional "satisfying sexual event" per month while at the same time “significantly increasing the risk of dizziness, somnolence, nausea, and fatigue,” according to the study.
Addyi has often been touted as the “female Viagra,” which in some ways has set it up for failure.
Viagra works in men by vasodilating the blood vessels to the penis so it can become engorged with blood to form an erection. The effect is purely mechanical. Viagra is only taken when needed.
Sexual desire in women is far more complicated. Women must first have increased desire and arousal to have sex.
Addyi is intended to work on a women’s biological libido, or her mind, by increasing the activity of the neurochemical serotonin in the brain.
It does not dilate blood vessels in the vagina to create engorgement, though this does occur naturally when a woman is aroused. Increased blood flow to a woman's vagina will not lead to having more sexual encounters for women like it does for men.
And unlike Viagra, Addyi must be taken every day, similar to antidepressants, which is what it was originally targeted to treat.
1) As FDA approves 'pink Viagra' for women, controversy persists. Los Angeles Times.com. Retrieved March 31, 2016.
2) "Female Viagra" Doesn't Work, Says Study. Shape.com. Retrieved March 31, 2016.
3) Jaspers, Loes MD. Efficacy and Safety of Flibanserin for the Treatment of Hypoactive Sexual Desire Disorder in Women. A Systematic Review and Meta-Analysis. JAMA Intern Med. Published online February 29, 2016.