PT-141 vs Melanotan-2
Approved libido peptide vs unregulated tanning peptide — they are not the same thing
PT-141
Melanocortin-receptor agonist that works on desire in the brain, not blood flow in the pelvis. FDA-approved as Vyleesi for premenopausal HSDD.
Best for
Best when libido is the actual goal. FDA-approved (Vyleesi) for HSDD; cleaner side-effect profile.
Read full pageMelanotan-2
The unregulated tanning peptide. Cheaper and more effective on libido than MT-1, but the side effect profile and mole-change risk make this the riskier of the two.
Best for
No legitimate medical use case at this point. The libido effect overlaps with PT-141 but melanocytic mole risk, priapism, and a worse side-effect profile make it the wrong tool when PT-141 exists.
Read full pageKey difference
Same family (melanocortin agonists) but PT-141 is selective for the libido pathway and avoids the pigmentation pathway. Melanotan-2 hits both indiscriminately, which is why people use it to tan and why it carries the melanoma worry.
Evidence quality
PT-141
Regulator-approvedFDA-approved in 2019 for HSDD in premenopausal women based on the RECONNECT trials (Palatin Technologies, two Phase 3 studies with about 1,200 women combined). The female indication is the licensed one; male use is entirely off-label but the central mechanism transfers. Long-term data beyond a year is thin.
Melanotan-2
AnecdotalNo completed Phase 3 trials. Melanotan-2 was studied in the 1990s as an erectile dysfunction candidate before being abandoned in favour of bremelanotide (PT-141), which has cleaner pharmacology. All current use is grey-market and unregulated. Case reports in dermatology journals document melanoma in MT-2 users; the relationship is concerning but not formally proven.
Not sure which one fits? Open both full pages and read the contraindications first — they are usually the deciding factor.