PT-141 vs Melanotan II: the honest comparison
PT-141 (bremelanotide) is FDA approved for sexual dysfunction and has a clean mechanistic target; Melanotan II is broader (affects pigmentation and sexual function but less selectively). For sexual-function goals specifically, PT-141 is the right compound. For tanning research, Melanotan II is the only option — at meaningful safety cost.
Side-by-side facts
| PT-141 | Melanotan II | |
|---|---|---|
| Class | Melanocortin receptor agonist (MC3R / MC4R) | Synthetic alpha-melanocyte stimulating hormone (α-MSH) analog |
| Half-life | Approximately 2 hours | Approximately 33 hours |
| Typical dose | 0.5–2 mg (500–2000 mcg) per dose, on demand | Loading: 250–500 mcg daily. Maintenance: 500–1000 mcg 1–2x weekly. |
| Category | Libido / sexual health | Melanocortin agonist |
| FDA status | FDA approved as Vyleesi for hypoactive sexual desire disorder (HSDD) in premenopausal women. | Not FDA approved. Banned in several countries for consumer use. Research use only in the US. |
| Storage | Lyophilized refrigerated. | Lyophilized refrigerated. |
What they have in common
Both are synthetic melanocortin-receptor agonists derived from alpha-MSH. Both can produce transient nausea and facial flushing. Both have effects on sexual arousal via central melanocortin pathways.
When to pick PT-141
Pick PT-141 when the target is sexual function. It is FDA approved (as Vyleesi) for hypoactive sexual desire disorder in premenopausal women and has a cleaner, more selective receptor profile. Pigmentation effects are minimal at therapeutic doses.
When to pick Melanotan II
Pick Melanotan II only for pigmentation-related research goals. Melanotan II activates MC1R (pigmentation) more strongly than PT-141, producing the characteristic tanning effect — but it also produces moles/naevi, stronger nausea, and has been associated with increased melanoma risk concerns in observational data.
Can you stack them?
Not meaningfully — both act on overlapping melanocortin receptors, and stacking them amplifies side effects without adding mechanism.
The two compounds
Track either compound on iPhone
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See the app →Frequently asked questions
What is the main difference between PT-141 and Melanotan II?
Selectivity. PT-141 targets MC3R/MC4R (sexual function) more cleanly; Melanotan II hits MC1R (pigmentation) harder. That selectivity difference is why PT-141 has an FDA approval and Melanotan II does not.
Can you stack PT-141 and Melanotan II?
Not meaningfully — both act on overlapping melanocortin receptors, and stacking them amplifies side effects without adding mechanism.
Which is better, PT-141 or Melanotan II?
PT-141 (bremelanotide) is FDA approved for sexual dysfunction and has a clean mechanistic target; Melanotan II is broader (affects pigmentation and sexual function but less selectively). For sexual-function goals specifically, PT-141 is the right compound. For tanning research, Melanotan II is the only option — at meaningful safety cost.
When should I pick PT-141?
Pick PT-141 when the target is sexual function. It is FDA approved (as Vyleesi) for hypoactive sexual desire disorder in premenopausal women and has a cleaner, more selective receptor profile. Pigmentation effects are minimal at therapeutic doses.
When should I pick Melanotan II?
Pick Melanotan II only for pigmentation-related research goals. Melanotan II activates MC1R (pigmentation) more strongly than PT-141, producing the characteristic tanning effect — but it also produces moles/naevi, stronger nausea, and has been associated with increased melanoma risk concerns in observational data.
Are PT-141 and Melanotan II FDA approved?
PT-141: FDA approved as Vyleesi for hypoactive sexual desire disorder (HSDD) in premenopausal women. — Melanotan II: Not FDA approved. Banned in several countries for consumer use. Research use only in the US.
Educational use only. Peptide Protocol is an informational tool. Nothing on this page constitutes medical advice. Many peptides are prescription-only or restricted in your jurisdiction. Always consult a licensed healthcare professional before injecting any compound.