Comparison
Ipamorelin vs. Melanotan II
Two peptides side-by-side — identity, evidence base, legal status and known adverse events.
Identity
Category
Growth
Research other
CAS no.
170851-70-4
121062-08-6
Molecular weight
711.86 g/mol
1024.18 g/mol
Half-life
2 h
1 h
Sequence
Aib-His-D-2-Nal-D-Phe-Lys-NH2Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2Mechanism of action
Ipamorelin
Ipamorelin is a selective agonist at the GH secretagogue receptor (GHSR-1a). Compared to GHRP-2 and GHRP-6 its selectivity for the growth-hormone axis is higher; ACTH, cortisol and prolactin are not significantly stimulated in clinical studies. This selectivity was the main reason for its development over older GHRPs.
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.
Evidence base
Highest evidence
Human RCT
Human trial
Studies
4
5
of which in humans
3
5
Effects recorded
3
4
Open conflicts
1
0
Documented adverse events
1
3