What Side Effects Can Women Experience With PT-141?

PT-141 most often causes nausea, flushing, headache and soreness where you inject. In the largest trials in premenopausal women with low sexual desire, about 40% felt nauseated and about 20% felt flushed, and most reactions were mild or moderate. PT-141 also briefly raises blood pressure and slows heart rate after each dose, so women with uncontrolled high blood pressure or known heart disease should not use it.

What are the most common side effects?

The best numbers come from the FDA label for Vyleesi, the prescription form of bremelanotide (PT-141). The label pools two 24-week trials with 627 women on active treatment and 620 on placebo pooled FDA label table. About 40.0% of treated women felt nauseated compared with 1.3% on placebo. About 20.3% felt flushed compared with 0.3%. About 13.2% had a reaction where they injected compared with 8.4%, often pain, redness or bruising. About 11.3% had headache compared with 1.9%, and 4.8% vomited compared with 0.2%.

A smaller group reported cough, fatigue, hot flush, tingling or prickling feeling in the skin (called paresthesia in the label), dizziness and stuffy nose. Each affected about 2 to 3% of treated women, all higher than placebo pooled FDA label table.

How bad do they feel and how long do they last?

Most side effects were mild or moderate in the two RECONNECT trials, which randomized 1,267 premenopausal women for 24 weeks of as-needed use RECONNECT results. Nausea usually started within one hour after a dose and lasted about two hours timing summary. About 8% stopped treatment because of nausea and about 2% because of headache. Stopping for vomiting, flushing or injection reactions happened in about 1% or less discontinuation data.

These trials studied premenopausal women with diagnosed low desire using the drug as needed, so they give less information about other ages, menopause stages or long-term daily use.

Who should avoid PT-141 for safety reasons?

PT-141 raises blood pressure for a short time and lowers heart rate after each dose FDA safety warnings. The FDA label lists uncontrolled high blood pressure or known heart and blood vessel disease as reasons not to use it. The label also warns about focal hyperpigmentation, which means darker patches can form on the skin. NIH reviewers noted the same skin darkening among uncommon reactions, along with severe nausea and vomiting and higher blood pressure readings NIH overview.

You can list blood pressure, heart history and any new skin color changes in the HOD quiz so a clinician can review whether PT-141 fits.