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What Is PT-141? Benefits, Research & Safety
An FDA-approved melanocortin receptor agonist for treatment of hypoactive sexual desire disorder in premenopausal women.
Also known as:
Bremelanotide
Vyleesi
UK summary: Bremelanotide is FDA-approved as Vyleesi for HSDD in premenopausal women in the US, but is not licensed in the UK. Cardiovascular effects (blood-pressure rise) are documented. Sport status uncertain; confirm before competition.
Quick Facts
Category
Sexual Health & Tanning
Half-Life
Approximately 2.7 hours
UK Status
Not approved. Available only through specialist channels or as research compound.
EU Status
Not approved by EMA. Not available as licensed medicine.
Overview
PT-141, now known by its approved name bremelanotide and sold under the brand name Vyleesi, is a melanocortin receptor agonist derived from Melanotan II research. Unlike its parent compound, PT-141 was specifically developed to target sexual function without significant tanning effects.
Bremelanotide represents a significant advancement in sexual medicine as the first FDA-approved treatment specifically for hypoactive sexual desire disorder (HSDD) in premenopausal women. Its approval in 2019 provided a new treatment option for a condition affecting a substantial proportion of women.
The peptide works through a fundamentally different mechanism than existing erectile dysfunction treatments. While PDE5 inhibitors like sildenafil act on peripheral blood flow, PT-141 works centrally through melanocortin receptors in the brain, affecting the neural pathways involved in sexual arousal and desire.
PT-141 has also been investigated for male erectile dysfunction, though it is not currently approved for this indication. Research continues into potential applications and optimisation of delivery methods.
As an approved medication (Vyleesi), bremelanotide is available by prescription in the United States. It is not currently approved in the UK or EU, where it remains a research compound or may be available through specialist channels.
Evidence standards summary
PT-141 — evidence and risk at a glance
Twenty standard modules scored against the Peptide Authority evidence grading methodology. Missing modules indicate the field has not yet been characterised editorially — treat absences as uncertainty rather than reassurance.
01Evidence snapshot
BModerate human evidenceOverall grade against our evidence grading methodology.
Bremelanotide is FDA-approved as Vyleesi for HSDD in premenopausal women in the US, but is not licensed in the UK. Cardiovascular effects (blood-pressure rise) are documented. Sport status uncertain; confirm before competition.
02Human evidence grade
AStrong human evidenceStrength of evidence from published human trials.
03Preclinical evidence grade
AStrong human evidenceAnimal-model and in-vitro evidence quality.
04Regulatory status
- UK: Not approved. Available only through specialist channels or as research compound.
- EU: Not approved by EMA. Not available as licensed medicine.
- Notes: PT-141 (bremelanotide/Vyleesi) is FDA-approved in the United States for HSDD in premenopausal women since 2019. It is not approved in UK or EU. WADA prohibits its use in competitive sport.
05Approved medical uses
- Hypoactive sexual desire disorder (HSDD) in premenopausal women (FDA-approved as Vyleesi in the US; NOT MHRA-licensed in the UK).
06Unapproved / promotional claims
- Safer than Viagra for erectile dysfunction.
- Works for everyone with no responder variability.
- Available routinely on UK prescription.
- Safe to combine with PDE5 inhibitors or recreational stimulants.
07Common internet claims
- Marketed online as a unisex 'sexual arousal' peptide.
- Sold by grey-market clinics on the FDA approval for the US-only Vyleesi indication.
- Promoted as a Viagra alternative for men with normal vascular function.
08Claim vs evidence
| Claim | Evidence | Human evidence? | Regulatory concern | Safer wording |
|---|---|---|---|---|
| “FDA-approved for sexual dysfunction” | A | Yes | Low | Vyleesi is FDA-approved for HSDD in premenopausal women in the US; this is not the same as UK MHRA approval. |
| “Available in the UK on prescription” | E | No | High | PT-141 / bremelanotide is not a UK-licensed medicine; some specialist routes may exist but not via standard NHS prescription. |
| “Safer than Viagra” | E | No | High | Comparative-safety claims need comparative trials. PDE5 inhibitors have substantial UK clinical use; bremelanotide has its own cardiovascular profile. |
| “Works for everyone” | C | Limited | Moderate | Trial response rates are moderate; significant non-responder fraction. |
09Safety uncertainty score
Moderate
Safety profile partly characterised; some signals from observational or preclinical data.
10Known adverse signals
- Transient blood-pressure rise (documented; major reason for FDA dose-frequency limits).
- Nausea, flushing, headache (common in trials).
- Skin hyperpigmentation with repeated use.
- Contraindicated in uncontrolled hypertension or cardiovascular disease.
11Drug-interaction uncertainty
Moderate
Some interaction data published; check with a prescriber for your specific medicines.
12Anti-doping status
WADA: Sport status unclearWADA strict-liability framing applies.
13UK legal position
UK: Unlicensed (UK)
Not approved. Available only through specialist channels or as research compound.
Read the full UK legal guide → Are peptides legal in the UK?
14EU legal position
Not approved by EMA. Not available as licensed medicine.
15What this page cannot tell you
- Whether a UK-purchased vial actually contains bremelanotide at the labelled concentration.
- Whether off-label male ED use carries the same safety profile as licensed female-HSDD use.
- How it interacts with PDE5 inhibitors (sildenafil, tadalafil) — not formally studied.
- Whether you have undiagnosed cardiovascular risk that would make the BP rise dangerous.
16Last reviewed
17Citation quality score
BModerate human evidenceQuality of the sources we cite, graded against the evidence grading methodology.
18Research gaps
- Male ED Phase 3 trials not published despite extensive promotion.
- Long-term cardiovascular safety beyond ~12 months unstudied.
- Combination safety with PDE5 inhibitors uncharacterised.
- No UK regulatory submission pathway active.
19Safer alternatives / established care pathways
- GP review for ED — licensed PDE5 inhibitors (sildenafil, tadalafil) are first-line, available NHS in selected groups, widely available privately.
- GP / psychosexual therapy referral for HSDD in women — talking therapy is NICE first-line.
- Cardiovascular risk assessment before any pharmacological sexual-health intervention.
20Doctor discussion prompts
Questions to ask a qualified clinician
These are starter questions you can adapt for a GP, specialist, pharmacist, or anti-doping advisor. The aim is to help you have a better-informed conversation — not to replace one.
- Is PT-141 / bremelanotide licensed in the UK?
- What licensed UK alternatives exist for the sexual-health concern I'm asking about?
- Do I have cardiovascular risk factors that would make bremelanotide unsuitable?
- If accessed privately, what is the supply-chain provenance?
Discovery & History
PT-141 emerged from research into Melanotan II at the University of Arizona. During clinical trials of Melanotan II for tanning, researchers observed significant effects on sexual function, including spontaneous erections in men and increased arousal in women.
Recognizing the therapeutic potential, Palatin Technologies acquired rights to develop a derivative specifically targeting sexual dysfunction. PT-141 was designed as a metabolite of Melanotan II with reduced pigmentation effects but retained activity at melanocortin receptors involved in sexual function.
Clinical development proceeded through multiple trials for both male erectile dysfunction and female sexual dysfunction. Initial development for ED was complicated by blood pressure effects observed with intravenous and intranasal administration.
The focus shifted to female hypoactive sexual desire disorder, where subcutaneous administration showed efficacy with an acceptable safety profile. Phase III trials (RECONNECT studies) demonstrated statistically significant improvements in desire and reduction in distress.
In 2019, the FDA approved bremelanotide (Vyleesi) for HSDD in premenopausal women, making it the first centrally-acting treatment for this condition. The approval came with a boxed warning regarding nausea and blood pressure effects.
Research continues into potential applications including male sexual dysfunction, though no additional approvals have been granted.
Mechanism of Action
PT-141 works through activation of melanocortin receptors, particularly MC4R, in the central nervous system:
**Central Melanocortin Pathway Activation**
PT-141 activates MC4R and MC3R in hypothalamic and limbic brain regions involved in sexual behavior:
- Direct effects on arousal centres in the hypothalamus
- Modulation of dopaminergic pathways involved in desire and motivation
- Influences on oxytocinergic systems linked to bonding and arousal
- Integration of desire, arousal, and pleasure circuits
**Mechanism Distinct from PDE5 Inhibitors**
Unlike sildenafil and similar drugs:
- Works on central desire and arousal rather than peripheral blood flow
- Effective in both men and women through central pathways
- Addresses desire/motivation aspects rather than purely physical function
- Does not require sexual stimulation to be present initially
**Receptor Selectivity**
PT-141 has modifications compared to Melanotan II that reduce:
- MC1R activity (less pigmentation effect)
- Duration of action
- Systemic exposure
However, it retains:
- MC4R agonism (sexual function)
- Some MC3R activity
- Sufficient potency for therapeutic effect
Researched Benefits
Based on preclinical and clinical research findings:
- 1Increased sexual desire in women with HSDD (approved indication)
- 2Reduced distress associated with low sexual desire
- 3Enhanced sexual arousal independent of peripheral mechanisms
- 4Potential efficacy in male erectile dysfunction (research)
- 5Works through novel central mechanism
- 6On-demand use (not daily medication)
Claim vs Evidence
How popular claims about PT-141 stack up against the current research, graded using our public evidence grading methodology.
| Claim | Evidence | Human evidence? | Regulatory concern | Safer wording |
|---|---|---|---|---|
| “FDA-approved for sexual dysfunction” | A | Yes | Low | Vyleesi is FDA-approved for HSDD in premenopausal women in the US; this is not the same as UK MHRA approval. |
| “Available in the UK on prescription” | E | No | High | PT-141 / bremelanotide is not a UK-licensed medicine; some specialist routes may exist but not via standard NHS prescription. |
| “Safer than Viagra” | E | No | High | Comparative-safety claims need comparative trials. PDE5 inhibitors have substantial UK clinical use; bremelanotide has its own cardiovascular profile. |
| “Works for everyone” | C | Limited | Moderate | Trial response rates are moderate; significant non-responder fraction. |
Theoretical Dosing & Protocols
⚠️ Educational Only: The following information is derived from research literature and is not a prescription or recommendation. No standardised human dosing exists. Always consult a qualified healthcare professional.
| Theoretical Dosage | 1.75 mg subcutaneous injection (approved dose for women) |
| Frequency | As needed, at least 45 minutes before anticipated sexual activity |
| Duration | Maximum 8 doses per month (per approved labeling) |
| Notes | Vyleesi is FDA-approved for HSDD in premenopausal women. Use is on-demand, not daily. Not approved for use in men or postmenopausal women. Should be prescribed by a healthcare professional familiar with the medication. |
Administration Routes
Routes studied in research settings (educational only):
- Subcutaneous injection (approved route)
- Intranasal (studied but not approved due to blood pressure effects)
| Half-Life | Stability |
|---|---|
| Approximately 2.7 hours | Commercial product (Vyleesi) has defined stability per manufacturer specifications |
Safety Profile & Known Risks
Commonly Reported Side Effects
- Nausea (40% in trials, often diminishes with use)
- Flushing
- Injection site reactions
- Headache
- Transient blood pressure increase
Rare Risks & Concerns
- Focal hyperpigmentation (darkening of skin, gums, or breast)
- Severe hypotension in certain patients
- Severe nausea requiring antiemetics
Contraindications
- Uncontrolled hypertension
- Cardiovascular disease
- Concurrent use of naltrexone (drug interaction)
- Pregnancy (Category X)
- Breastfeeding
UK & EU Regulatory Context
🇬🇧 United Kingdom
Not approved. Available only through specialist channels or as research compound.
🇪🇺 European Union
Not approved by EMA. Not available as licensed medicine.
PT-141 (bremelanotide/Vyleesi) is FDA-approved in the United States for HSDD in premenopausal women since 2019. It is not approved in UK or EU. WADA prohibits its use in competitive sport.
Clinical Studies Summary
RECONNECT Phase 3 Trials
Pivotal trials demonstrating efficacy of bremelanotide for HSDD in premenopausal women, leading to FDA approval.
Sexual medicine journalsView on PubMed
Bremelanotide for Male Erectile Dysfunction
Early clinical research investigating PT-141 for male ED, showing efficacy but development not continued for this indication.
Urology journalsView on PubMed
Looking for PT-141?
Source research-grade PT-141 from a trusted UK supplier — third-party tested with certificate of analysis.
View at SupplierFrequently Asked Questions
Questions to ask a qualified clinician about PT-141
These are starter questions you can adapt for a GP, specialist, pharmacist, or anti-doping advisor. The aim is to help you have a better-informed conversation — not to replace one.
- Is PT-141 / bremelanotide licensed in the UK?
- What licensed UK alternatives exist for the sexual-health concern I'm asking about?
- Do I have cardiovascular risk factors that would make bremelanotide unsuitable?
- If accessed privately, what is the supply-chain provenance?
UK regulatory & safety context
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