Cosmetic & dermatologic
Melanotan II
A synthetic melanocortin analogue originally studied as a tanning and sexual-health drug. Abandoned as a medicine and sold illegally as a tanning product.
What it is
Melanotan II is a cyclic synthetic analogue of alpha-melanocyte-stimulating hormone. It was developed in the 1980s as a potential sunless tanning agent and studied for erectile dysfunction. It was never approved as a medicine, and unregulated tanning products sold under the name have caused documented harm in Europe and Australia. It is sold illegally in many countries.
How it works
- 1
Binds melanocortin receptors (MC1, MC3, MC4) rather than a single receptor, which explains its broad effects.
- 2
MC1 receptor activation in the skin stimulates melanocytes to produce darker pigment.
- 3
MC4 receptor activation in the brain affects appetite and sexual arousal pathways.
- 4
Because it is not selective, side effects across multiple systems are expected rather than incidental.
What it's studied for
Reported and studied effects
- Visible skin darkening within days of use in early studies
- Increased sexual arousal reported in small trials
- Nausea, flushing and appetite loss in most participants
- Darkening of moles was noted, which complicates skin-cancer surveillance
Research protocol notes
Research context onlyResearch context only — there is no approved protocol and no legitimate supply. Phase I studies used injected microgram doses with monitoring. Products sold online are unregulated, frequently mislabelled, and have been linked to serious adverse events.
These figures are described so you can understand what researchers did. They are not a dose, a schedule, or a suggestion — and they are not a substitute for a doctor.
Possible side effects and contraindications
Safety profile
Possible side effects
- Nausea and vomiting, common in trials
- Facial flushing and spontaneous erections
- Darkening of existing moles and new pigmented lesions
- Changes in blood pressure and heart rate reported
- Cases of severe skin reactions and systemic illness from unregulated products
Contraindications and cautions
- History of melanoma or atypical moles
- Pregnancy and breastfeeding
- Cardiovascular disease
- Any use of unregulated product — this is the main practical contraindication
A side-effect list is never complete, and these are not the only situations that warrant caution. Anything unexpected, or anything you are unsure about, should be discussed with a doctor before use.
Evidence assessment
Only small, old phase I and pilot studies exist. Development stopped, no regulatory approval was pursued, and post-market harm reports outweigh any published benefit data.
References
- 01Dorr et al., Evaluation of Melanotan-II in a pilot phase-I clinical study, Life Sci 1996 — PubMed search
- 02Melanotan II safety concerns — PubMed literature search
- 03World Anti-Doping Agency — Prohibited List
References link to published literature, regulator pages or literature indexes. Where a link points to a search, it collects the peer-reviewed work on that molecule rather than a single study.
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