Comparison
Melanotan II vs. Vasopressin
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
no data
Molecular weight
1024.18 g/mol
1084.23 g/mol
Half-life
1 h
no data
Sequence
Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2no data
Mechanism 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.
Vasopressin
Vasopressin binds V1 receptors (vasoconstriction, raising vascular resistance) and V2 receptors (renal water reabsorption via aquaporin channels). This raises blood pressure and acts antidiuretically. Desmopressin is the V2-selective synthetic analog.
Evidence base
Highest evidence
Human trial
Human RCT
Studies
9
0
of which in humans
5
0
Effects recorded
4
2
Open conflicts
1
0
Documented adverse events
6
1
Legal status
Full entries
Frequently asked questions
- What is the difference between Melanotan II and Vasopressin?
- Melanotan II is classified as "Research other", while Vasopressin 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. Vasopressin: Vasopressin (arginine vasopressin, antidiuretic hormone/ADH) is a cyclic nonapeptide hormone that regulates water balance and vascular tone. As Vasostrict it is approved to raise blood pressure in vasodilatory shock. This page contrasts both neutrally and source-based — with no usage or dosing recommendation.
- Which peptide is better supported by science, Melanotan II or Vasopressin?
- The highest available evidence level is "Human trial" for Melanotan II and "Human RCT" for Vasopressin. 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 Vasopressin in Germany and the United States?
- Germany: Melanotan II — Unapproved, Vasopressin — Prescription. United States: Melanotan II — Unapproved, Vasopressin — Prescription. These are factual summaries with source and review date on the individual pages.