No reports describing the use flibanserin in human pregnancy have been located. Although the animal data suggest low risk, the absence of human pregnancy data prevents an assessment of the embryo-fetal risk.
No reports describing the use of flibanserin during human lactation have been located.
The molecular weight (about 390) and the long terminal half-life (about 11 hours) suggest that the drug will be excreted into breast milk. However, the extensive metabolism and high plasma protein binding (about 98%) should limit the amount in milk. Sedation does occur when this drug is taken and, if used during breastfeeding, is a potential risk for a nursing infant. The most common (≥2%) adverse effects in adults were dizziness, somnolence, nausea, fatigue, insomnia, and drug mouth (1). If a woman is taking this drug while breastfeeding, her infant should be monitored for these effects.
Flibanserin (Addyi)
Pregnancy Recommendation:No Human Data—Animal Data Suggest Low Risk
Breastfeeding Recommendation:No Human Data—Potential Toxicity
Flibanserin is an antidepressant that is given orally. It is indicated for the treatment of premenopausal women with acquired, generalized hypoactive sexual desire disorder as characterized by low sexual desire that causes marked distress or interpersonal difficulty and is not due to a coexisting medical or psychiatric condition, problems within the relationship, or the effects of medications or other drug substance. The drug is extensively metabolized to at least 35 metabolites, most of them occurring in low concentrations in plasma. Two metabolites, both inactive, have plasma concentrations similar to the parent drug. Plasma protein binding, mainly to albumin, is about 98% and the terminal half-life is about 11 hours (1).
Animal Data: Reproduction studies have been conducted in rats and rabbits. In rats, the no adverse effect level for embryo-fetal toxicity was 15 times the clinical exposure from the recommended human dose (CERHD). Rabbits received doses that were 4-16 times the CERHD. No treatment-related teratogenic effects were observed in fetuses with these doses. Increases in resorptions and decreased fetal weights were observed at doses that were 8 times the CERHD, but significant maternal toxicity was also noted.
Significant increases in mammary tumors (adenoacanthoma and adenocarcinomas) and in hepatocellular adenomas/carcinomas were observed in female mice. No increases in mammary tumors were seen in male mice but significant increases in hepatocellular carcinomas were noted. Fertility studies in female and male rats were negative (1).
Placental Transfer: It is not known if flibanserin crosses the human placenta. The molecular weight (about 390) and the long terminal half-life suggest that the drug will cross to the embryo-fetus. However, the extensive metabolism and high plasma protein binding may decrease the exposure to the parent drug.