Comparison
Argireline vs. Bremelanotide
Two peptides side-by-side — identity, evidence base, legal status and known adverse events.
Identity
Category
Cosmetic
Research other
CAS no.
616204-22-9
189691-06-3
Molecular weight
888.99 g/mol
1025.18 g/mol
Half-life
no data
2.7 h
Sequence
Ac-Glu-Glu-Met-Gln-Arg-Arg-NH2Ac-Nle-c[Asp-His-D-Phe-Arg-Trp-Lys]-OHMechanism of action
Argireline
Argireline is a synthetic hexapeptide whose sequence corresponds to the N-terminus of the SNAP-25 protein. In vitro it has been shown to competitively inhibit SNARE complex formation (necessary for vesicle fusion in neurotransmitter release). Topical application is intended — given very limited skin permeation — to attenuate cholinergic signalling at the neuromuscular endplate. The effect is orders of magnitude weaker than intramuscular botulinum toxin; the clinical translatability of the in-vitro observations to the skin microenvironment is contested.
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
3
5
of which in humans
2
5
Effects recorded
3
3
Open conflicts
1
0
Documented adverse events
1
2