Side effects guide

PT-141 Side Effects

Melanocortin agonist

PT-141 has real human trial and label data behind its side-effect profile. Across the RECONNECT Phase 3 trials and its long-term extension, the most common reactions were nausea, flushing, and headache, mostly mild to moderate, with nausea affecting a substantial share of users and occasionally leading people to stop.[1][2]

Reviewed for accuracy · Last reviewed July 7, 2026

Reported side effects

COMMONNausea · Flushing · Injection-site reactions · Headache
LESS COMMONTransient blood-pressure increase · Focal darkening of skin (with repeated use)

The label also documents a transient increase in blood pressure and a decrease in heart rate after each dose, usually resolving within about 12 hours, which is why it is not recommended in uncontrolled hypertension or known cardiovascular disease and why dosing frequency is capped. With repeated dosing, focal darkening of the skin (including the face and gums) has been reported, more often in people with darker skin or who dose frequently.

Seek medical attention ifYou notice a severe or persistent rise in blood pressure, chest pain, or signs of an allergic reaction.

Managing side effects

Nausea is the effect most likely to be bothersome and is often worst early. Because of the transient blood-pressure effect, dosing more often than the label allows is discouraged, and cardiovascular concerns are a reason to involve a doctor rather than self-manage.

FAQ

How common is nausea with PT-141?It is the most common side effect. In the long-term extension of the Phase 3 program roughly 40% of users reported nausea, usually mild to moderate, and it was among the more frequent reasons for discontinuation.
Does PT-141 affect blood pressure?Yes, transiently. The label reports a short-lived increase in blood pressure and decrease in heart rate after dosing, usually resolving within about 12 hours, and cautions against use in uncontrolled hypertension or cardiovascular disease.

References

  1. Long-Term Safety and Efficacy of Bremelanotide for Hypoactive Sexual Desire DisorderObstetrics & Gynecology · 2019 · PMID 31599847 · DOI 10.1097/AOG.0000000000003514
  2. VYLEESI (bremelanotide) injection: DailyMed labelDailyMed (U.S. National Library of Medicine) · current · DailyMed setid 8c9607a2-5b57-4a59-b159-cf196deebdd9 · NDA 210557
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This page is an independent educational reference and is not medical advice. Talk to a doctor before starting any compound.