Sexual health is an unusual goal here because one of the peptides discussed for it is genuinely FDA-approved, while the other is an unapproved gray-market compound whose libido effect is essentially a side effect. Both act on melanocortin receptors in the brain rather than on blood flow, but they differ sharply in evidence and risk, so sorting them that way is the most useful thing this page can do.
Reviewed for accuracy · Last reviewed July 8, 2026The compounds below are the ones most discussed for sexual health. Each links to its full profile, where the dosing, side effects, and sources live. They are ordered roughly by how much human evidence sits behind them, not by a claim that any one works.
The gap between these two is large. PT-141 is an approved medicine with Phase 3 trials behind it, though only for a narrow group (premenopausal women with HSDD), so broader use is off-label. Melanotan II has no approval for any use, and its effect on sexual function is an off-target consequence of a non-selective melanocortin agonist.
Melanotan II carries risks that are not trivial: priapism (a prolonged, painful erection that can cause permanent damage), blood-pressure changes, and mole darkening. Agencies in the US, UK, and elsewhere have warned against it. Independently sourced PT-141 vials are the same molecule as Vyleesi but are not tested to the same standard.
This page is an independent educational reference and is not medical advice, and does not indicate any approval status for any use. Talk to a doctor before starting any compound.