PeptidesInfo

Peptide profile · Melanocortin receptor agonist (cyclic heptapeptide, melanotan II metabolite)

PT-141

Also known as: Bremelanotide, Vyleesi, Melanocortin receptor agonist

Bremelanotide, marketed as Vyleesi, is an FDA-approved melanocortin agonist for hypoactive sexual desire disorder in premenopausal women. Its use in men and for erectile dysfunction is not approved.

Established evidenceFDA-approved for this use
Abstract peptide-chain illustration for the PT-141 profile

Evidence level

Established

Two phase 3 randomised placebo-controlled trials (RECONNECT, ~1,200 women) showed statistically significant but modest improvements in desire and distress scores over 24 weeks. Evidence in men, postmenopausal women and for erectile dysfunction is older, smaller and did not lead to approval.

Regulatory status (US)

FDA-approved for this use

FDA-approved (June 2019) as bremelanotide (Vyleesi) for acquired, generalised hypoactive sexual desire disorder in premenopausal women. Not approved for men or postmenopausal women. Products sold online as "PT-141" are not the approved drug.

Mechanism (proposed)

Activates melanocortin receptors (MC4R and others) in the central nervous system, influencing sexual desire and arousal pathways; unlike PDE5 inhibitors it does not act primarily on genital blood flow.

Studied for: HSDD in premenopausal women (phase 3, approved), Erectile dysfunction in men (early studies, discontinued), Female sexual arousal disorder (phase 2)

Full research analysis

PT-141: Mechanism, Approved Use, Benefits, and Limitations

PT-141 (bremelanotide) is FDA-approved as Vyleesi for low sexual desire in premenopausal women, with modest benefits and a lot of nausea. Its use in men — the way it is mostly marketed online — was abandoned in development. Here is what the trials actually showed.

Read the analysis

What PT-141 is

PT-141 is bremelanotide, a cyclic peptide that activates melanocortin receptors in the brain. It was originally noticed as a metabolite of the tanning peptide melanotan II, developed for sexual dysfunction, and approved by the FDA in 2019 as Vyleesi for one indication: acquired, generalised hypoactive sexual desire disorder in premenopausal women[3].

Where the evidence stands

The two RECONNECT phase 3 trials enrolled about 1,200 premenopausal women and found small but statistically significant improvements in desire and associated distress compared with placebo over 24 weeks[1]. Nausea affected roughly 40% of treated women. That is established evidence — for that indication.

The story in men is different. Early-2000s studies of PT-141 in erectile dysfunction showed erectile responses[2], but the programme was halted, partly over blood-pressure effects, and no approval for men followed. Online marketing of "PT-141 for men" rests on those older, small studies.

Regulatory position

FDA-approved as a prescription drug for premenopausal women with HSDD; not approved for men, postmenopausal women, or "libido enhancement" generally. The label contraindicates use in uncontrolled hypertension or known cardiovascular disease.

Safety summary

Nausea in roughly 40% of treated women (about 13% required antiemetics in trials), flushing, injection-site reactions and headache are common. The label warns of transient increases in blood pressure and decreases in heart rate after each dose (contraindicated in uncontrolled hypertension or known cardiovascular disease) and of focal skin hyperpigmentation, especially with more than eight doses per month.

Frequently asked questions

Is PT-141 the same as Vyleesi?
PT-141 is the development code for bremelanotide, which is the active ingredient of the FDA-approved product Vyleesi. Products sold online as "PT-141" are not Vyleesi and are not approved.
Is PT-141 approved for men?
No. Early studies in men with erectile dysfunction were halted, partly over blood-pressure effects, and no approval for men exists.
How well does bremelanotide work?
In the phase 3 trials, improvements in desire and distress were statistically significant but modest, and about 40% of women experienced nausea.

References

Numbered in order of first use. Study type is shown for every source; see our methodology for how we rank evidence.

  1. 1.

    Kingsberg SA, Clayton AH, Portman D, et al.. Bremelanotide for the Treatment of Hypoactive Sexual Desire Disorder: Two Randomized Phase 3 Trials Obstetrics & Gynecology, 2019.

    Randomized controlled trialPremenopausal women with acquired, generalised HSDDn = 1267

    Result: Statistically significant improvements in FSFI desire domain and FSDS-DAO distress item vs placebo at 24 weeks; effect sizes modest.

    Limitations: High nausea rates; subjective endpoints; sponsor-run.

    ↑ back to text
  2. 2.

    Rosen RC, Diamond LE, Earle DC, Shadiack AM, Molinoff PB. Evaluation of the safety, pharmacokinetics and pharmacodynamic effects of subcutaneously administered PT-141, a melanocortin receptor agonist, in healthy male subjects and in patients with an inadequate response to Viagra International Journal of Impotence Research, 2004.

    Human studyHealthy men and men with ED unresponsive to sildenafil

    Result: Erectile responses observed; blood-pressure and nausea effects noted.

    Limitations: Small, early-phase; programme in men later halted; never approved.

    ↑ back to text
  3. 3.

    FDA approves new treatment for hypoactive sexual desire disorder in premenopausal women U.S. Food and Drug Administration, 2019.

    Regulatory source

    Result: Approval of bremelanotide (Vyleesi) with labelled warnings on blood pressure and hyperpigmentation.

    ↑ back to text

Review status: Editorially reviewed against primary sources. This article was fact-checked against the primary sources listed in the references by our editorial team, and it has not been reviewed by a licensed clinician. It is educational content, not medical advice. Read our editorial policy and methodology. Spotted an error? Tell us.

Profile by Tristen Ta. Published August 15, 2026; updated August 15, 2026.

Articles about PT-141

Search all →
Benefits4 min read

Are Peptides Worth It? A Framework for Deciding

Whether a peptide is worth it depends on four things: what benefit is proven, in whom, for how long, and whether the effect lasts after you stop. Here is that framework applied to every peptide we cover.

Benefits8 min read

Peptide Benefits: What the Evidence Actually Supports

Peptides are credited with dozens of benefits. Some are proven in large trials, some are modest and real, and some have never been tested in a person. This is every major benefit claim, sorted by how strong the human evidence is.

Research analysis4 min read

PT-141: Mechanism, Approved Use, Benefits, and Limitations

PT-141 (bremelanotide) is FDA-approved as Vyleesi for low sexual desire in premenopausal women, with modest benefits and a lot of nausea. Its use in men — the way it is mostly marketed online — was abandoned in development. Here is what the trials actually showed.

Regulation6 min read

FDA-Approved, Off-Label, Investigational, and Unapproved Peptides

The regulatory status of a peptide is a fact about a decision, not a verdict on the evidence. This guide explains the four categories, what compounding rules changed in 2023–2025, and where every peptide we cover currently sits.

Foundations4 min read

What Are Peptides? A Research-Based Introduction

Peptides are short chains of amino acids that range from approved blockbuster drugs to unregulated 'research chemicals'. Here is what the word actually covers, how peptides differ from proteins and small-molecule drugs, and why the category tells you nothing about evidence.