PT-141
FDA ApprovedAn FDA-approved melanocortin receptor agonist for hypoactive sexual desire disorder (HSDD) in premenopausal women. Acts centrally rather than on vascular mechanisms. Phase 3 RECONNECT trials demonstrated efficacy.
Bremelanotide · Vyleesi
18 human studies
- Preclinical
- 14%
- Clinical
- 51%
Based on 35 cited sources
clinically demonstrated · moderate confidence
Demonstrated effect magnitude — not a recommendation or safety claim.
Research Depth 84: two identical independent Phase 3 RCTs (RECONNECT 301/302, 31599840, N=1267) plus a Phase 2b dose-finding RCT (27181790, N=327) and a responder analysis (31277966); total development-program human N ~3500 (35147466), direct population/route/outcome match for HSDD; no published meta-analysis of RCTs so 1A capped at "≥2 independent RCTs" (30) and 1B at low-RoB RCT without a high-confidence systematic review (18). Mechanism 86: MC4R is a validated named target with binding plus functional agonism and knockout/antagonist abolition of the pro-sexual effect (2A 40), proximal mPOA->dopamine pathway partially mapped (2B 20), human dose-response shown across Phase 1/2 (14999221, 14963471) and confirmed in vivo (2C 16, 2D 10). Plausibility 89: full mechanism->desire surrogate (FSFI-D)->clinical distress/SSE chain each supported in RCTs (3A 34), fully coherent with melanocortin sexual-motivation biology (3B 25), class analogy via parent melanocortin agonist Melanotan-II (9679884; 3C 17), tightly scoped single-mechanism claim (3D 13). Global Coverage 62: replicated across two independent Phase 3 trials but heavily sponsor-linked (Palatin/AMAG) and geographically narrow (96.6% US sites in RECONNECT) -> 4A 22, 4B 12; ~35 citations of diverse angles (4C 18); single-regulator FDA approval, no EMA (4D 10). Community Experience 73: broad discussion across clinical and research-peptide venues (5A 24) over >7 years (5B 26), broadly consistent themes (5C 14); nausea (40%) is a notable but mild/moderate recurring AE with no serious safety signal (5D 9). Effectiveness clinical basis, score 44, moderate confidence: RECONNECT effect sizes are small (FSFI-D ~+0.35, FSDS-DAO ~-0.33; E1 10) but meet the predefined MCID per responder analysis (31277966; E2 10) on patient-reported desire/distress outcomes (E3 12), superior to placebo with no head-to-head vs flibanserin (E4 12).
PT-141 (bremelanotide) is an FDA-approved melanocortin receptor agonist that works centrally in the brain rather than through peripheral vasodilation. It is the first approved treatment that directly increases sexual desire.
How It Works (Simplified)
PT-141 acts through central nervous system pathways to enhance sexual desire:
Crosses the blood-brain barrier and binds MC4R in the hypothalamus, triggering dopamine release in sexual motivation circuits.
Unlike Viagra, PT-141 increases sexual desire itself rather than just physical response - it generates the “wanting” through dopaminergic activation.
MC4R activation also triggers spinal cord pathways that produce genital arousal responses independent of local blood flow mechanisms.
Effects begin 30-60 minutes after injection and peak within 1-4 hours. Short 2.7-hour half-life means effects are time-limited.
Key Research: Kingsberg SA et al. (2019) Phase 3 RECONNECT trials demonstrated significant improvement in FSFI-D and FSDS-DAO scores in premenopausal women with HSDD. PMID:31599840
Important Limitations
- FDA-approved only for premenopausal women with HSDD
- Not approved for male erectile dysfunction despite early trials
- High nausea incidence (40%) limits tolerability
- Transient blood pressure increases require monitoring
- Use limited to 8 doses per month due to cardiovascular effects
- Contraindicated with uncontrolled hypertension or cardiovascular disease
Reported positives
- Effective for sexual desire enhancement in both sexes
- FDA-approved formulation (Vyleesi) validates mechanism
- Effects distinct from PDE5 inhibitors — acts on desire not just function
- Some users report emotional/mood enhancement
Reported negatives
- Nausea is very common and can be severe
- Facial flushing and skin darkening reported
- Effects inconsistent and dose-dependent
- Headaches common side effect
“Unique mechanism targeting desire rather than mechanics. Community discussions span both clinical and research peptide contexts.”
Self-reported, unverified accounts — not clinical evidence and no substitute for the cited research. Anecdotes are prone to selection bias and placebo effects.
| NCT ID | Title | Peptide | Phase | Status | Completion |
|---|---|---|---|---|---|
| NCT06867835 | Single Dose of Vyleesi in Lactating Female Subjects to Measure the Concentration of Bremelanotide in Breast Milk Lactating Mother | PT-141 | Phase 4 | Completed | Nov 2025 |
| NCT06565611 | A Phase 2 Study Evaluating the Co-Administration of Bremelanotide With Tirzepatide for the Treatment of Obesity Obesity | PT-141 | Phase 2 | Active | Feb 2025 |
| NCT05709444 | A Phase IIb, Multicenter, Open-Label, Prospective Study of Bremelanotide in Diabetic Kidney Disease Kidney Disease | PT-141 | Phase 2 | Completed | Apr 2024 |
| NCT04943068 | A Phase 3, Bridging, Multicenter, Randomized, Double-blind, Placebo-controlled, Parallel-group Trial to Evaluate the Efficacy and Safety of Subcutaneously Administered Bremelanotide in Premenopausal Women With Hypoactive Sexual Desire Disorder (With or Without Decreased Arousal) Hypoactive Sexual Desire Disorder | PT-141 | Phase 3 | Completed | May 2023 |
| NCT04179734 | Role of the Melanocortin-4 Receptor in Hypoactive Sexual Desire Disorder Hypoactive Sexual Desire Disorder | PT-141 | Phase 4 | Completed | Oct 2020 |
| NCT03973047 | Study to Evaluate Rate of Nausea in Healthy Premenopausal Female Subjects Treated With Single Dose of Bremelanotide Alone or With Zofran Nausea | PT-141 | Phase 1 | Completed | Jul 2019 |
| NCT02338960 | 2. Study to Evaluate the Efficacy/Safety of Bremelanotide in Premenopausal Women With Hypoactive Sexual Desire Disorder Hypoactive Sexual Desire Disorder | PT-141 | Phase 3 | Completed | Aug 2016 |
| NCT02333071 | 1. Study to Evaluate the Efficacy/Safety of Bremelanotide in Premenopausal Women With Hypoactive Sexual Desire Disorder Hypoactive Sexual Desire Disorder | PT-141 | Phase 3 | Completed | Jul 2016 |
| NCT01382719 | Bremelanotide in Premenopausal Women With Female Sexual Arousal Disorder and/or Hypoactive Sexual Desire Disorder Female Sexual Arousal Disorder, Hypoactive Sexual Desire Disorder | PT-141 | Phase 2 | Completed | Sep 2012 |
| NCT00425256 | Evaluate the Safety and Efficacy of Bremelanotide in Women With Female Sexual Arousal Disorder (FSAD) Sexual Arousal Disorder | PT-141 | Phase 2 | Completed | May 2007 |
Single Dose of Vyleesi in Lactating Female Subjects to Measure the Concentration of Bremelanotide in Breast Milk
A Phase 2 Study Evaluating the Co-Administration of Bremelanotide With Tirzepatide for the Treatment of Obesity
A Phase IIb, Multicenter, Open-Label, Prospective Study of Bremelanotide in Diabetic Kidney Disease
A Phase 3, Bridging, Multicenter, Randomized, Double-blind, Placebo-controlled, Parallel-group Trial to Evaluate the Efficacy and Safety of Subcutaneously Administered Bremelanotide in Premenopausal Women With Hypoactive Sexual Desire Disorder (With or Without Decreased Arousal)
Role of the Melanocortin-4 Receptor in Hypoactive Sexual Desire Disorder
Study to Evaluate Rate of Nausea in Healthy Premenopausal Female Subjects Treated With Single Dose of Bremelanotide Alone or With Zofran
2. Study to Evaluate the Efficacy/Safety of Bremelanotide in Premenopausal Women With Hypoactive Sexual Desire Disorder
1. Study to Evaluate the Efficacy/Safety of Bremelanotide in Premenopausal Women With Hypoactive Sexual Desire Disorder
Bremelanotide in Premenopausal Women With Female Sexual Arousal Disorder and/or Hypoactive Sexual Desire Disorder
Evaluate the Safety and Efficacy of Bremelanotide in Women With Female Sexual Arousal Disorder (FSAD)
Based on clinical pharmacodynamic studies: effects begin roughly 30-60 minutes after subcutaneous injection. Vyleesi is taken at least 45 minutes before anticipated sexual activity per its FDA labeling.
PMID:14999221Peak effects typically occur within 1-4 hours of administration. Studies showed increased desire and arousal during this window. Nausea (40%) peaks and typically resolves within this period.
PMID:14999221Effects may persist for 4-12 hours in some individuals. Duration is variable. The relatively short half-life means effects are time-limited compared to longer-acting therapies.
Effects generally resolve within 24 hours. PT-141 is used on an as-needed basis (at least 45 minutes before anticipated activity), not daily. Do not use more than once in 24 hours.
PMID:14999221Research-based observations
This timeline reflects observations from published clinical and preclinical studies. Individual responses may vary significantly. This is not a guarantee of effects or a dosing schedule. Consult qualified healthcare providers for personalized guidance.
Good Signs (6 indicators)
Warning Signs (4 indicators)
Bad Signs (7 indicators)
For Research Evaluation Only
These quality indicators are general guidelines based on typical peptide characteristics. Professional laboratory testing (HPLC, mass spectrometry) provides definitive quality verification. This checklist is for initial visual evaluation only.
BPC-157
CompatibleDifferent mechanisms with no known interaction. BPC-157's gastroprotective effects may theoretically help with PT-141's nausea, though this is speculative.
Thymosin-Alpha-1
CompatibleNon-overlapping mechanisms (immune modulation vs melanocortin signaling). No known contraindications.
Semaglutide
CautionBoth can cause nausea. PT-141 commonly causes nausea (40% incidence). GI adverse events may be additive. Monitor tolerability.
Tirzepatide
CautionSimilar caution as semaglutide. Both affect GI function and can cause nausea. Monitor for additive GI effects.
Melanotan-II
AvoidBoth are melanocortin receptor agonists with overlapping activity. PT-141 is derived from Melanotan II. Combining would provide redundant stimulation with increased adverse event risk.
Research Note: Interaction data is based on published literature, mechanistic understanding, and theoretical considerations. Most peptide combinations lack direct clinical study. This information is for educational purposes only and does not constitute medical advice. Always consult qualified healthcare providers.
Key Studies Cited
Full reference list available on request. All citations link to PubMed for verification.
This dossier synthesizes available evidence from peer-reviewed literature, regulatory documents, and clinical trial registries. Evidence strength ratings follow a modified GRADE approach.
For complete methodology details, see our Methodology page.
Important Disclaimer
This dossier is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before making health decisions.
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