Library / Sexual health

Bremelanotide

Also known as PT-141, Vyleesi

Approved medicine

Melanocortin receptor agonist peptide developed from melanotan II. Approved in the US only for low sexual desire in premenopausal women; trial effects were modest.

Not approved in Australia. Bremelanotide is not on the Australian Register of Therapeutic Goods. Only a prescriber can decide whether a medicine suits you and at what dose. This page is information, not a recommendation.

Background

A synthetic cyclic peptide developed by Palatin Technologies from melanotan II, which had been made at the University of Arizona. It was approved in the United States in 2019 as Vyleesi.

How it is thought to work

It activates several melanocortin receptors, mainly MC4R in the brain and MC1R on pigment cells. How it improves sexual desire is not known.

What is claimed, and the evidence

Claim	Evidence	Notes
Low sexual desire causing distress (acquired, generalised HSDD) in premenopausal women	Approved use	FDA approved in 2019 based on two 24 week randomised trials (n = 1,267). Improvements over placebo were statistically significant but small, and an independent reanalysis described the benefits as modest.
Sexual desire or performance in men, or in postmenopausal women	No published evidence	Not approved; the label states it is not indicated for men, for postmenopausal women or to enhance sexual performance.
Libido boost in anyone, tanning or weight loss	No published evidence	Online claims for unapproved 'PT-141' products; no supporting approval or trial evidence.

Side effects

Effect	How often	Notes
Nausea	Common	40% vs 1% with placebo; 13% needed anti nausea medicine and 8% stopped treatment.
Flushing	Common	20% vs 0.3% with placebo.
Injection site reactions	Common	13% vs 8% with placebo.
Headache	Common	11% vs 2% with placebo.
Vomiting	Uncommon	About 5%.
Transient rise in blood pressure and fall in heart rate Serious	Common	Blood pressure rose by up to 6/3 mmHg for up to 12 hours after each dose.
Focal darkening of skin, face, gums or breasts Serious	Uncommon	About 1% with up to 8 doses a month; did not always resolve.

Warnings

Not for people with uncontrolled high blood pressure or known heart disease.
Skin and gum darkening may not reverse.
Not approved by the TGA; unapproved 'PT-141' products are not the same as the approved pen. Unapproved products bought online are not checked by any regulator for purity, sterility or strength; they may be contaminated, underdosed, overdosed or contain a different substance to the label.

Phase 3 trials

RECONNECT

Phase 3, Completed, published. 1,437 participants, 24 weeks. NCT02333071

Population: Premenopausal women with hypoactive sexual desire disorder. Two trials, NCT02333071 and NCT02338960.
Arms: Bremelanotide 1.75 mg as needed, at most once in 24 hours; Placebo
Primary outcome: Change in FSFI desire score.
Results: Desire score rose 0.35 points more than placebo across both trials.
Safety: Nausea about 40%. 8.1% stopped because of nausea.
Source: Kingsberg SA et al. Obstet Gynecol 2019;134:899-908.

Doses in these trials were given under medical supervision.

Regulatory status

Australia: Not found on the ARTG. Not specifically listed in the Poisons Standard (June 2026).
United States: FDA approved (Vyleesi, 2019) for acquired generalised hypoactive sexual desire disorder in premenopausal women.

Sources

Also in Sexual health

From the VialOwl library, reviewed 26 September 2026. For education and general information. It is not medical advice and not a recommendation to use Bremelanotide.