Peplens

Melanotan-2

Early human

Synthetic cyclic analogue of alpha-MSH; non-selective melanocortin receptor agonist (MC1R/MC3R/MC4R/MC5R) · Also known as Melanotan II, MT-2, MT-II, melanocortin receptor agonist

Overview

Melanotan-2 is a synthetic, non-selective melanocortin receptor agonist developed as a successor to Melanotan-1, acting on MC1R (driving tanning), MC4R (linked to appetite suppression and sexual arousal), and other melanocortin receptors. It is marketed online as an injectable for tanning and sometimes libido, but it is NOT FDA-approved for any use and is sold as an unlicensed research chemical. Its broader receptor activity means more pronounced melanocortin side effects than Melanotan-1, and it carries notable documented safety signals. Health agencies in multiple countries have warned against it. Human efficacy and long-term safety for cosmetic use are not established, and any claimed benefits should be treated as unproven.

Commonly Reported Uses

These are uses commonly discussed or marketed by users and vendors — not a list of proven or approved benefits, and not a recommendation.

  • Skin tanning / increased pigmentation (marketed claim; NOT an approved use)
  • Libido / sexual arousal (reported MC4R-mediated effect; NOT an approved use — the related approved melanocortin drug for desire is bremelanotide/PT-141)
  • Appetite suppression (reported effect; unproven and unapproved for weight goals)

What to Track

Data points you and your clinician might monitor. For observation only — not a diagnostic protocol.

  • Skin — daily check-ins on tanning response and, importantly, any new or changing moles/naevi (case reports describe melanocytic/mole changes and melanoma)
  • Blood pressure and heart rate — cardiovascular effects (including hypertension) are documented; monitor especially with cardiovascular risk factors
  • Subjective — nausea, flushing, appetite suppression, spontaneous erections (common melanocortin effects)
  • Labs — if any muscle pain or dark urine occurs, creatine kinase and renal function (rhabdomyolysis and renal infarction have been reported in case reports) — seek urgent care, do not self-monitor a medical emergency
  • Body weight — smart-scale trend if appetite changes (contextual only)

Sources & References

  1. [1]Melanotan II — Wikipedia (mechanism, regulatory status, safety)
  2. [2]Melanotan II: a possible cause of renal infarction — review of the literature and case report (CEN Case Rep, 2020) — PMC
  3. [3]Changes of melanocytic lesions induced by Melanotan injections — PMC

Quick Reference

Class
Synthetic cyclic analogue of alpha-MSH; non-selective melanocortin receptor agonist (MC1R/MC3R/MC4R/MC5R)
Evidence Level
Early human
Reported Uses
3 listed
Tracking Metrics
5 suggested
Citations
3 sources

Safety & legal notes

NOT FDA-approved for any indication; sold as an unlicensed 'research use only' chemical, and multiple national health agencies (e.g. in the UK, Australia, and elsewhere) have issued warnings against melanotan injections. Notable safety signals reported in the literature include nausea, blood-pressure changes/hypertension, melanocytic (mole) changes and new dysplastic naevi, melanoma, and rare but serious case reports of rhabdomyolysis and renal infarction. Any new or changing pigmented lesion needs prompt dermatologic review. Athletes should verify current rules with their governing body. This is educational information, not a recommendation; consult a licensed clinician.

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