Melanotan I (afamelanotide) is a more selective MC1R agonist — the receptor most associated with pigmentation. Melanotan II is a broader, non-selective melanocortin agonist, hitting multiple receptor subtypes, which is why it's associated with additional effects (and why PT-141 was derived from it).
| Melanotan I | Melanotan II | |
|---|---|---|
| Selectivity | More selective (MC1R) | Broad (multiple MCRs) |
| Studied for | Pigmentation | Pigmentation + other MCR effects |
| Related to | — | PT-141 (Bremelanotide) |
Melanocortin agonists — MT-II especially — can cause nausea, flushing, and transient blood-pressure changes in research contexts, and both are research-only with limited long-term data. Our stacking guide flags Melanotan combinations as caution.
For the arousal-focused relative of MT-II, see PT-141 (Bremelanotide).
Both are typically sold in 10 mg vials. PepsTracker compares them across all 26 vendors on cost-per-mg with codes applied. Platinum Peptides carries both (MT-1 and MT-2), 15% off with pepstracker15.
Melanotan I is a more selective MC1R agonist studied for pigmentation, while Melanotan II is a broad, non-selective melanocortin agonist with additional effects. PT-141 was derived from Melanotan II.
Yes. PT-141 (Bremelanotide) is derived from Melanotan II; both act on melanocortin receptors, but PT-141 is studied for arousal and MT-II for pigmentation.
Melanotan II is broader-acting, while Melanotan I is more selective to the MC1R pigmentation receptor. Both are research-only with limited long-term data and carry cautions.