Comparison
Melanotan II vs. Sekretin
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
3055.5 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.
Sekretin
Secretin binds the Gs-coupled secretin receptor (SCTR) on pancreatic duct cells, opens CFTR chloride channels and triggers secretion of bicarbonate-rich pancreatic fluid and bile flow.
Evidence base
Highest evidence
Human trial
Human trial
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 Sekretin?
- Melanotan II is classified as "Research other", while Sekretin 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. Sekretin: Secretin is a 27-amino-acid hormone that regulates pancreatic bicarbonate secretion. As ChiRhoStim it is FDA-approved as a diagnostic agent (pancreatic function test, gastrinoma test, secretin-enhanced MRCP). This page contrasts both neutrally and source-based — with no usage or dosing recommendation.
- Which peptide is better supported by science, Melanotan II or Sekretin?
- The highest available evidence level is "Human trial" for Melanotan II and "Human trial" for Sekretin. 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 Sekretin in Germany and the United States?
- Germany: Melanotan II — Unapproved, Sekretin — Prescription. United States: Melanotan II — Unapproved, Sekretin — Prescription. These are factual summaries with source and review date on the individual pages.