Bothersome low libido, also known as hypoactive sexual desire disorder or HSDD, represents the most common sexual dysfunction in women. Difficult to treat, HSDD is a frustrating condition for women, their partners, and clinicians. Although testosterone has some utility in treating HSDD in postmenopausal women, it is effective only at supraphysiologic doses, its long-term safety profile is not well understood, and its use in women is not approved by the US Food and Drug Administration (FDA).
Neurotransmitters have important effects on the sexual response. While dopamine and norepinephrine can enhance sexual desire, serotonin can cause inhibition. Flibanserin (Addyi®), which initially had been investigated for its antidepressant qualities, appears to modulate neurotransmitters so as to, on balance, increase sexual desire.[2,3]
The FDA's approval of flibanserin to treat HSDD in premenopausal women on August 18, 2015, a decision associated with much controversy, represents a women's health landmark in that this medication is the first drug approved to treat female sexual dysfunction.[4,5]
Women and clinicians should be aware of several practical issues relevant to the use of flibanserin[2,3,6]:
The medication, taken as a 100-mg daily tablet, is not effective in all premenopausal women with HSDD. Among those women who do experience improvement in HSDD with flibanserin, the efficacy is incremental. Overall, compared with placebo, flibanserin increased the number of satisfying sexual events (SSEs) by only 0.5 to one per month. However, some 25% of women in the clinical trials experienced an increase of four or more SSEs with flibanserin, compared with 15% of those assigned to placebo.
Unlike the rapid effects of medications for male erectile dysfunction, the benefits of flibanserin in reducing HSDD are observed only after the first 4 weeks of daily treatment, with results peaking at 8 weeks. Flibanserin is not known to affect sexual arousal or orgasmic function.
To reduce side effects, which include drowsiness, hypotension, and syncope, flibanserin is taken at bedtime. Because liver disease, as well as concomitant use of alcohol or moderate to strong CYP3A4 inhibitors, is associated with an increased risk for these side effects, package labeling for Addyi® includes a boxed warning addressing these concerns, including that flibanserin users should not consume alcohol. Moderate and strong CYP3A4 inhibitors include certain oral antifungals, antibiotics, and antiretrovirals.
Only prescribers and pharmacists certified through an online course will be able to prescribe and dispense flibanserin, which should be available as soon as October of this year.
Medscape Ob/Gyn © 2015 WebMD, LLC
Any views expressed above are the author's own and do not necessarily reflect the views of WebMD or Medscape.
Cite this: First Female Sexual Dysfunction Drug: What to Know Before Prescribing - Medscape - Aug 20, 2015.