Melanotan I vs Melanotan II
Melanotan I vs Melanotan II — the original tanning peptides: one developed into an approved photoprotection therapy, the other the raw research compound. Here's a neutral, sourced side-by-side — no hype, every claim links to its evidence.
Melanotan I
ApprovedAlso: Afamelanotide, MT-1
Melanotan I is a man-made chemical that acts like a hormone in the body. It is a copy of a substance found in humans that controls skin color.
Melanotan II
ResearchAlso: Melanotan-2, MT II
Melanotan II is a synthetic cyclic heptapeptide and non-selective melanocortin receptor agonist (MC1R/MC3R/MC4R/MC5R). MC1R agonism darkens skin (tanning); MC4R effects increase libido and induce erections.
At a Glance
| Melanotan I | Melanotan II | |
|---|---|---|
| Research status | Approved | Preclinical |
| Highest-tier evidence | Peer-reviewed study | Peer-reviewed study |
| Research citations | 5 | 3 |
| Dosing routes | — | — |
| Receptor targets | — | MC1R, MC3R, MC4R, MC5R |
| Half-life | — | — |
| Known side effects | 10 | 11 |
Research Areas
Top preclinical research areas — cited studies for each.
Melanotan I
- Induces eumelanin production (tanning)
- Reduces phototoxic reactions in Erythropoietic Protoporphyria (EPP)
- Decreases recovery time from phototoxic reactions in EPP
- Improves quality of life in EPP patients
- Reduces weal formation in Solar Urticaria
Melanotan II
- Skin darkening (cosmetic)
- Increased libido/erectile effects
The Evidence
Key studies — click through to verify each on PubMed.
Melanotan I
5 sourced studies
- Source
PubChem - Compound - Afamelanotide
95/100Rated 95/100Source typePeer-reviewed studyIndependent sourcesstill being verifiedEvery claim links to the page it came from, and stronger sources rate higher. Full methodology → - Source
Afamelanotide for prevention of phototoxicity in erythropoietic protoporphyria.
2021 95/100Rated 95/100Source typePeer-reviewed studyIndependent sourcesstill being verifiedEvery claim links to the page it came from, and stronger sources rate higher. Full methodology → - Source
Label: SCENESSE- afamelanotide implant
95/100Rated 95/100Source typePeer-reviewed studyIndependent sourcesstill being verifiedEvery claim links to the page it came from, and stronger sources rate higher. Full methodology → - Source
Advances in the management of erythropoietic protoporphyria - role of afamelanotide.
95/100Rated 95/100Source typePeer-reviewed studyIndependent sourcesstill being verifiedEvery claim links to the page it came from, and stronger sources rate higher. Full methodology →
Melanotan II
3 sourced studies
- Source
TGA warning: tanning products containing melanotan
Guideline2023 Key study 70/100Rated 70/100Source typeRegulator or clinical registryIndependent sourcesstill being verifiedEvery claim links to the page it came from, and stronger sources rate higher. Full methodology → - Source
Melanotan-induced priapism: a hard-earned tan
CaseReport2019 60/100Rated 60/100Source typePeer-reviewed studyIndependent sourcesstill being verifiedEvery claim links to the page it came from, and stronger sources rate higher. Full methodology → - Source
Convergence of melatonin and serotonin (5-HT) signaling at MT2/5-HT2C receptor heteromers
95/100Rated 95/100Source typePeer-reviewed studyIndependent sourcesstill being verifiedEvery claim links to the page it came from, and stronger sources rate higher. Full methodology →
Decision Guide
How to Choose
Neither is a “winner” — they suit different goals. Compare the documented benefits and evidence above against what you’re actually trying to achieve, note the research status (approved vs research-stage), and read each full guide before deciding. Many people also stack peptides rather than pick one.
Source Melanotan I
Shop Melanotan ISource Melanotan II