Comparison
Melanotan II vs. Bremelanotide
Two peptides side-by-side — identity, evidence base, legal status and known adverse events.
Identity
Category
Research other
Research other
CAS no.
121062-08-6
189691-06-3
Molecular weight
1024.18 g/mol
1025.18 g/mol
Half-life
1 h
2.7 h
Sequence
Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2Ac-Nle-c[Asp-His-D-Phe-Arg-Trp-Lys]-OHMechanism of action
Melanotan II
Melanotan II binds non-selectively to all five melanocortin-receptor subtypes (MC1R-MC5R). Via MC1R in melanocytes, eumelanin synthesis is stimulated (pigmenting effect). Via MC4R and MC3R in the CNS, appetite, sexual function and blood pressure are modulated. The cyclic structure and D-amino acids increase stability compared to natural α-MSH.
Bremelanotide
Bremelanotide is a cyclic peptide that binds non-selectively to melanocortin receptors (MC1R through MC5R) — with highest affinity at MC4R in the central nervous system. The precise role of MC4R activation in sexual behaviour is not fully understood; animal data show effects on hypothalamic circuits. Peripheral effects (blood pressure, hyperpigmentation) are attributed to MC1R/MC2R.
Evidence base
Highest evidence
Human trial
Human RCT
Studies
9
5
of which in humans
5
5
Effects recorded
4
3
Open conflicts
1
1
Documented adverse events
6
2
Legal status
Full entries
Frequently asked questions
- What is the difference between Melanotan II and Bremelanotide?
- Melanotan II is classified as "Research other", while Bremelanotide is classified as "Research other". Melanotan II: Cyclic hepta-peptide and non-selective melanocortin-receptor agonist. Originally researched at the University of Arizona as a sun-protection concept — never approved as a medicine. Widespread on the black market; regulatory warnings for cardiovascular and oncological risks. Bremelanotide: Synthetic cyclic heptapeptide acting as a non-selective melanocortin-receptor agonist. FDA-approved in 2019 as Vyleesi for hypoactive sexual desire disorder (HSDD) in pre-menopausal women. This page contrasts both neutrally and source-based — with no usage or dosing recommendation.
- Which peptide is better supported by science, Melanotan II or Bremelanotide?
- The highest available evidence level is "Human trial" for Melanotan II and "Human RCT" for Bremelanotide. A higher evidence level means more robust data, but says nothing about suitability for an individual. The full body of evidence is on each peptide's own page.
- What is the legal status of Melanotan II and Bremelanotide in Germany and the United States?
- Germany: Melanotan II — Unapproved, Bremelanotide — Unapproved. United States: Melanotan II — Unapproved, Bremelanotide — Prescription. These are factual summaries with source and review date on the individual pages.