Bremelanotide (pt‑141) is a peptide that can boost sexual desire by activating brain pathways linked to the melanocortin system. In trials with pre‑menopausal women who have low sexual desire, it showed a modest improvement on questionnaires but caused nausea in about 40% of users. The overall benefit is limited and the studies are hard to interpret because of strong placebo effects and subjective outcome measures.

Female sexual response implies a deep intertwining between psychosocial and neurobiological mediators. Regulation of central melanocortin signaling may enhance sexual desire. In premenopausal women with hypoactive sexual desire disorder (HSDD), melanocortin receptor agonist bremelanotide (Vyleesi) has been hypothesized to trigger excitatory brain pathways. Hereby we summarize bremelanotide's proposed mechanism of action, pharmacokinetics, efficacy and safety data derived from clinical trials. A literature search of peer-reviewed publications on the current evidence on the pharmacotherapy with bremelanotide was performed using the PubMed database. Bremelanotide appears to be moderately safe and well-tolerated; the most common adverse reaction is nausea (40%). Although data from clinical trials demonstrated a significant change in validated questionnaires, the overall clinical benefit appears to be modest. However, these results should be interpreted in the light of the dramatic challenges in conducting well-designed clinical trials for female sexual dysfunction, due to the significant placebo effect of pharmacotherapy, and the frequent use of outcome measures that are likely to be highly susceptible to expectation biases, such as long periods of recall of sexual and emotional response.