Clinical1996
Pilot Phase 1 study: Melanotan II induced tanning in most volunteers; common side effects were facial flushing, nausea, increased appetite, and spontaneous penile erections.
Enhanced tanning with less sun exposure
anecdotal
FDA Approved 19 views
Melanotan
Overview
Melanotan II is an analog that is a derivative of a precursor of melanocyte stimulating hormone (a-MSH). It seeks out melanocortin receptors, primarily MC1R in the skin and MC4R in the brain. On the skin side, it ramps up tyrosinase within melanocytes, cranks out eumelanin and revs up the handoff of that pigment to nearby keratinocytes. Translation: You tan with less sun and the color lasts longer. Melanocortin tone can also affect libido and appetite, so users may find themselves feeling extra lusty and a little less hungry. The molecule is 'cyclic' and very receptor efficient, so small amounts can give clear effects.
Last reviewed: 2026-08-18
Identity & Aliases
Also known as
Melanotan I (MT-1)Melanotan II (MT-2)Bremelanotide (PT-141, related)Afamelanotide (Scenesse, related)alpha-MSH analog
Status: Research compound - Melanocortin receptor agonist
CAS75921-69-6
PubChem92432Full composition (formula, molecular weight, sequence) in Quick Facts →
Research Areas
Skin pigmentation and tanningSexual desire and function (MC4R pathway)Erythropoietic protoporphyria (afamelanotide)Photoprotection
Available Evidence
Human
A pilot Phase 1 study of Melanotan II in healthy volunteers produced tanning in most subjects, with side effects including facial flushing, nausea, and penile erections. The related peptide bremelanotide (PT-141) was FDA-approved in 2019 (Vyleesi) for acquired hypoactive sexual desire disorder in premenopausal women based on two randomized Phase 3 RECONNECT trials, and the melanocortin agonist afamelanotide (Scenesse) is FDA-approved for erythropoietic protoporphyria. Melanotan II itself has no approved use.
Animal
Animal studies established that melanocortin MC1R agonism drives eumelanin production via the cAMP/MITF pathway, and phototoxicity models supported afamelanotide development.
In Vitro
Melanotan II is a non-selective agonist at MC1R, MC3R, MC4R and MC5R; MC1R activation in melanocytes triggers melanogenesis.
Uncertain
Long-term skin safety of repeated melanotan use (nevus changes, melanoma risk) is not established by controlled studies, though concerning case reports exist; weight-loss and general anti-aging claims are unproven.
Key Studies & Findings
Clinical2019
Two randomized Phase 3 trials (RECONNECT) showed bremelanotide significantly improved sexual desire and distress in premenopausal women with HSDD, supporting FDA approval.
Benefits & Effects
Side Effects & Safety
Limitations & Open Questions
Melanotan II has no approved medical use; direct clinical evidence is limited to a small pilot study plus pharmacovigilance reports, and most real-world use is unregulated; long-term effects on moles, skin pigmentation and cardiovascular safety are not established.
Pharmacology
Melanotan II is a cyclic alpha-MSH analog that activates melanocortin receptors (MC1R-MC5R), stimulating eumelanin synthesis in melanocytes. The related compound bremelanotide (PT-141) targets MC4R for sexual-desire effects and is given by subcutaneous injection (Vyleesi, 1.75 mg as needed). There is no approved dosing for melanotan II.
Reported Research Dosing
Reported values from research literature and community protocols. Educational reference only — not a dosing recommendation or medical advice.
0.5-1 mg Loading then maintenance
Route: SC
Half-life: ~1 hour
Research Protocols
Initial Tanning (Light Skin)
- Dose
- 0.25mg
- Frequency
- 2x daily
- Route
- Subcutaneous injection
Maintenance Tanning
- Dose
- 0.5mg
- Frequency
- 1x daily
- Route
- Subcutaneous injection
Enhanced Pigmentation
- Dose
- 0.5mg
- Frequency
- 2x daily
- Route
- Subcutaneous injection
Photoprotection Only
- Dose
- 0.25mg
- Frequency
- 1x daily
- Route
- Subcutaneous injection
Research protocols are for educational purposes only. Always consult qualified medical professionals.
Frequently Asked Questions
Is Melanotan II FDA-approved?
No. Melanotan II is not approved; only the related peptides bremelanotide (Vyleesi, for HSDD) and afamelanotide (Scenesse, for erythropoietic protoporphyria) are FDA-approved.
What are the known side effects of Melanotan II?
In the pilot clinical study, flushing, nausea, increased appetite, and spontaneous erections were reported; unregulated use has also been linked to skin-pigmentation changes and concerning nevus/skin-lesion reports.
Research Citations
1
Melanotan Tanning Injection: A Rare Cause of Priapism.
Mallory CW, Lopategui DM, Cordon BH (2021)
2
Melanotan-induced priapism: a hard-earned tan.
Dreyer BA, Amer T, Fraser M (2019)
3
Melanotan II: a possible cause of renal infarction: review of the literature and case report.
Peters B, Hadimeri H, Wahlberg R, Afghahi H (2020)
4
Melanotan-associated melanoma.
Paurobally D, Jason F, Dezfoulian B, Nikkels AF (2011)
5
Melanotan-II reverses memory impairment induced by a short-term HF diet.
Wekwejt P, Wojda U, Kiryk A (2023)
+ 20 more citations
Related Resources
Quick Facts
Formula
C50H69N15O9
Molecular Weight
1024.18
Sequence
MACPSLACCLLGLLALTSACYIQNCPLGGKRAALDLDMRKCLPCGPGGKGRCFGPSICCADELGCFVGTAEALRCQEENYLPSPCQSGQKPCGSGGRCATAGICCSPDGCRTDPACDPESAFSER
Mechanism
Activates MC1R (tanning) and MC4R (sexual arousal)
Safety Information
Research compound only. Not approved as a drug in the United States. Regular skin checks recommended due to mole darkening effects. Not a substitute for sun protection.
Citations
251.Melanotan Tanning Injection: A Rare Cause of Priapism.
Mallory CW, Lopategui DM, Cordon BH (2021)
2.Melanotan-induced priapism: a hard-earned tan.
Dreyer BA, Amer T, Fraser M (2019)
3.Melanotan II: a possible cause of renal infarction: review of the literature and case report.
Peters B, Hadimeri H, Wahlberg R, Afghahi H (2020)
4.Melanotan-associated melanoma.
Paurobally D, Jason F, Dezfoulian B, Nikkels AF (2011)
5.Melanotan-II reverses memory impairment induced by a short-term HF diet.
Wekwejt P, Wojda U, Kiryk A (2023)
+ 20 more citations