PT-141 (Bremelanotide)
The Libido-Activating Peptide That Works from the Brain Down
What is PT-141 (Bremelanotide)?
PT-141, also known by its clinical name Bremelanotide, is a synthetic peptide analog of alpha-melanocyte-stimulating hormone (α-MSH). It was developed from Melanotan II and is approved for the treatment of hypoactive sexual desire disorder (HSDD) in premenopausal women under the brand name Vyleesi.
PT-141 works by activating melanocortin receptors, specifically MC3R and MC4R, in the brain. It is the first peptide-based therapy shown to improve sexual arousal and libido by acting on the central nervous system (CNS) rather than the vascular system. It is studied extensively in both male and female models for its pro-sexual, neuroregulatory, and mood-enhancing effects.
How Does PT-141 Work?
Unlike PDE5 inhibitors like Viagra that work via the vascular system, PT-141 targets the melanocortin system within the brain. Specifically, it binds to MC3R and MC4R receptors in areas responsible for sexual desire, reward, and motivation.
Mechanism of Action:
- Stimulates melanocortin-4 receptors (MC4R) in the hypothalamus
- Enhances dopaminergic and sexual arousal pathways
- Bypasses cardiovascular effects seen in traditional erectile dysfunction drugs
- Works in both male and female models, increasing libido and sexual satisfaction
Benefits of PT-141
🔥 Sexual Arousal & Desire
- Increases libido and sexual motivation in both men and women
- Enhances erectile function in males (including those unresponsive to PDE5 inhibitors)
- Approved for use in female sexual dysfunction (HSDD)
🧠 Central Nervous System Modulation
- Acts directly on CNS libido pathways, not the bloodstream
- Promotes dopaminergic tone and sexual anticipation
- May improve mood, motivation, and intimacy behaviors
💊 Advantages Over Traditional Therapies
- Works even in individuals who do not respond to Viagra or Cialis
- No significant blood pressure or vascular side effects at therapeutic doses
- Onset of action within 30 to 60 minutes, with effects lasting up to 12 hours
PT-141 vs Melanotan II vs PDE5 Inhibitors
| Feature | PT-141 | Melanotan II | Viagra/Cialis |
|---|---|---|---|
| Mechanism | MC3R/MC4R stimulation | Broad MC receptor activity | PDE5 inhibition |
| Libido Enhancement | Strong | Moderate–Strong | None |
| Erection Support | Strong | Moderate | Strong |
| Side Effects | Nausea, flushing (rare) | Nausea, tanning, fatigue | Headache, hypotension |
| Mood Effects | Positive (CNS-based) | Mixed | None |
| Ideal Use | Sexual desire & arousal | Tanning + libido | Erectile function only |
Suggested Dosage & Protocol
Common Dosing Guidelines:
- 1mg to 2mg via subcutaneous (SC) injection
- Can be administered 30 to 60 minutes before sexual activity
- Dosing should be limited to no more than 8 doses per month for FDA-approved applications
Intranasal Delivery (Research Use):
- 500mcg to 1000mcg, intranasal spray formulation (less bioavailable than injectable)
Safety Profile of PT-141
PT-141 is FDA approved for female HSDD, with a well-characterized safety profile. Side effects are typically mild and dose-dependent.
Common Side Effects:
- Nausea or flushing
- Mild headache
- Transient increase in blood pressure (resolves within 12 hours)
Less Common Effects:
- Injection site reactions (redness, swelling)
- Darkening of gums or skin (rare)
- Fatigue or yawning
Reference:
- Clayton AH et al., “Safety Profile of Bremelanotide Across the Clinical Development Program.” J Womens Health, 2021.0191. https://pubmed.ncbi.nlm.nih.gov/35147466/
Storage Instructions
- Store lyophilized PT-141 at 2–8°C in a dry, dark location
- Reconstitute with bacteriostatic water for injection
- Use within 14–30 days post-reconstitution
Ideal Stack Recommendations
PT-141 pairs well with:
- Oxytocin – to enhance bonding, intimacy, and emotional responsiveness
- NAD+ – for energy and mood support during sexual activity
- Selank or Semax – to reduce performance anxiety and improve focus
- GHK-Cu – for skin support if tanning side effects from MT-II are undesired
Is PT-141 Right for Your Research?
If your research explores sexual motivation, CNS modulation, female arousal disorders, or dopamine signaling, PT-141 is a powerful, FDA-approved tool with broad CNS engagement and specific MC receptor targeting. Its effects extend beyond sexual health into mood, behavior, and relationship-based studies.
Final Thoughts
PT-141 (Bremelanotide) represents the next generation of sexual health peptides, focusing on brain-level desire and arousal rather than vascular mechanics. Its unique action on melanocortin receptors, favorable safety profile, and utility across genders make it an essential compound in behavioral, neuroendocrine, and sexual wellness research.
Lab of RAD offers research-grade PT-141 peptide to support your work in performance, intimacy, and behavioral science.
⚠️ FDA Disclaimer
This content is provided for educational and research purposes only. PT-141 has not been evaluated or approved by the U.S. Food and Drug Administration (FDA) for uses outside of HSDD in women. It is not intended to diagnose, treat, cure, or prevent any disease.
Lab of RAD peptides are for laboratory research use only and are not for human consumption.