Melanotan II: The Tanning Peptide
Last updated: March 2026
Melanotan II is a synthetic analog of α-MSH (alpha-melanocyte-stimulating hormone), developed at the University of Arizona to stimulate melanin production for UV-free tanning by targeting melanocortin receptors MC1-R through MC5-R. Research dosing typically begins at 500 mcg subcutaneously. It is also the precursor to PT-141 (Bremelanotide), now FDA-approved for sexual dysfunction.
🧪 Buy Melanotan II at Swiss Chems →(typical)
Targets
Method
📋 On this page
What Is Melanotan II?
Melanotan II is a synthetic peptide analog of α-MSH (alpha-melanocyte-stimulating hormone). Developed at the University of Arizona, it stimulates melanocortin receptors to produce melanin and darken skin without UV exposure.
Stimulates melanocytes to produce eumelanin, providing a tan without UV exposure. Useful for people who can't tan normally.
Binds to melanocortin receptors (MC1R-MC5R) with varying affinity. MC1R is primarily responsible for melanin production.
Melanotan II's sexual function effects led to the development of PT-141 (Bremelanotide) — FDA approved for hypoactive sexual desire disorder.
Typically administered via subcutaneous injection. Nasal spray formulations have also been used in research.
MT-I vs MT-II vs PT-141 — How They Differ
Three peptides share an α-MSH backbone but target different melanocortin receptors, treat different conditions, and carry different risk profiles. Confusing them is the most common mistake people make in this category.
| Compound | Receptor Selectivity | Approved Indication | Primary Effect |
|---|---|---|---|
| MT-I (Scenesse / afamelanotide) | MC1R-selective | FDA-approved 2019 — erythropoietic protoporphyria (EPP) | Skin eumelanin → visible-light photoprotection |
| MT-II (this page) | Non-selective — MC1R, MC3R, MC4R, MC5R | None (research chemical; FDA-unapproved) | Tanning + libido + nausea + erection priming |
| PT-141 (Vyleesi / bremelanotide) | MC4R / MC3R (CNS) | FDA-approved 2019 — HSDD in premenopausal women | Central libido response (no skin tanning) |
Quick mental model: MT-I = skin only. MT-II = everything, everywhere (the original "research tanner" with all the unwanted side effects). PT-141 = brain only, for sexual response. They share a parent α-MSH structure but they are not interchangeable, and "Melanotan" by itself almost always means MT-II in the gray market.
Safety Profile
Known side effects and concerns with Melanotan II use.
What the Research Shows
Key Takeaways
- Synthetic α-MSH analog
- Produces tanning without UV
- Developed at U of Arizona
- Precursor to FDA-approved PT-141
- SubQ or nasal administration
- Not FDA approved
- Side effects: nausea, flushing, vomiting
- Dermatology concerns about moles
- Long-term safety unknown
- Quality varies widely
🔬 Verified Research Source
Third-party tested compounds from Swiss Chems — one of the most trusted research suppliers.
Affiliate link — supports HighPeptides at no extra cost. All Swiss Chems products include third-party lab testing certificates.
🔗 Related Resources
Research-Grade Peptides
Third-party tested compounds with certificates of analysis. Used by researchers worldwide.
Browse Swiss Chems →Affiliate link — supports HighPeptides at no extra cost.
Want the Complete Protocol Guide?
Dosing schedules, interaction warnings, and cycle protocols for 50+ compounds — all in one place.
Get the Guide →
This page is for educational purposes only. Melanotan II is not FDA approved. It is a research chemical with significant side effects. Always consult a healthcare provider.