Quick facts
- Class
- Endogenous melanocortin peptide
- Roles
- Pigmentation, inflammation, appetite, sexual function
- Acts on
- Melanocortin receptors (MC1R–MC5R)
- Analogs
- Afamelanotide, melanotan, bremelanotide (PT-141)
- Approval
- Endogenous hormone; its drug analogs are regulated separately
- Derived from
- Pro-opiomelanocortin (POMC)
- Receptors
- Melanocortin receptors MC1R–MC5R
Key takeaways
- Alpha-MSH is the body's natural melanocortin hormone, cleaved from the precursor POMC.
- It drives skin pigmentation (via MC1R) and has broad anti-inflammatory roles.
- Through MC4R it influences appetite and sexual function — the pathway PT-141 targets.
- The well-known synthetic peptides — afamelanotide, melanotan, and PT-141 — are analogs of it.
- It is an endogenous hormone, not a marketed drug in itself.
Overview
Alpha-melanocyte-stimulating hormone (α-MSH) is a natural peptide hormone, cleaved from the precursor protein POMC, that acts across a family of melanocortin receptors. It is the endogenous signal that the well-known synthetic peptides imitate — afamelanotide (Melanotan I), Melanotan II, and PT-141 (bremelanotide) are all melanocortin analogs.[2]
How it works
- Pigmentation. Acting on the MC1R receptor in skin, α-MSH stimulates melanin production — the basis of tanning biology.[2]
- Anti-inflammation. It has broad anti-inflammatory and protective actions across many tissues, including the eye and skin.[1][5]
- Appetite & sexual function. Through central melanocortin receptors (notably MC4R), the system influences appetite and sexual response — the pathway PT-141 targets.[4]
Research & benefits
α-MSH is a long-standing research subject rather than a marketed product. Studies span its role in pigmentation and the pleiotropic effects of the α-MSH/MC1R interaction beyond skin color,[2] its non-pigmentary anti-inflammatory actions in the skin,[5] the multifunctional ocular melanocortin system,[1] and the underlying signalling mechanisms.[4] Practically, its importance for most readers is as the biology behind the melanocortin drugs — the tanning and sexual-desire analogs derived from it.[3]
Safety & status
α-MSH itself is an endogenous hormone, not a sold product, so the practical safety considerations attach to its synthetic analogs — see the afamelanotide, Melanotan II, and PT-141 guides, which range from an FDA-approved drug to an unapproved tanning chemical. Alpha-MSH is not itself marketed as an approved therapy.
Frequently asked questions
What is alpha-MSH?
Alpha-MSH (alpha-melanocyte-stimulating hormone) is a natural melanocortin peptide hormone derived from POMC. It drives skin pigmentation, has anti-inflammatory roles, and influences appetite and sexual function through melanocortin receptors.
How is alpha-MSH related to melanotan and PT-141?
Melanotan I (afamelanotide), Melanotan II, and PT-141 (bremelanotide) are all synthetic analogs of alpha-MSH — engineered melanocortin agonists designed to imitate or refine its natural effects on pigmentation and sexual desire.
Can you buy alpha-MSH?
Alpha-MSH itself is an endogenous hormone rather than a marketed product; the practical considerations attach to its drug analogs, which range from an FDA-approved implant (afamelanotide) to an unapproved tanning chemical (Melanotan II).
References
Each source links to its original record — peer-reviewed studies, regulator pages, or reference texts, labelled by type. We summarize findings neutrally; a citation is a reference, not an endorsement, and not a claim that its authors reviewed this page.
- Wu CS, Cioanca AV, Gelmi MC, et al. The multifunctional human ocular melanocortin system. Prog Retin Eye Res. 2023. Peer-reviewed study
- Herraiz C, Martínez-Vicente I, Maresca V. The alpha-melanocyte-stimulating hormone/melanocortin-1 receptor interaction: A driver of pleiotropic effects beyond pigmentation. Pigment Cell Melanoma Res. 2021. Peer-reviewed study
- Takeuchi S, Takahashi S, Okimoto R, et al. Avian melanocortin system: alpha-MSH may act as an autocrine/paracrine hormone. Ann N Y Acad Sci. 2003. Peer-reviewed study
- Eves PC, Haycock JW. Melanocortin signalling mechanisms. Adv Exp Med Biol. 2010. Peer-reviewed study
- Böhm M, Schiller M, Luger TA. Non-pigmentary actions of alpha-melanocyte-stimulating hormone — lessons from the cutaneous melanocortin system. Cell Mol Biol. 2006. Peer-reviewed study
- Suominen A, Saldo Rubio G, Ruohonen S, et al. α-Melanocyte-stimulating hormone alleviates pathological cardiac remodeling via melanocortin 5 receptor. EMBO Rep. 2024. Peer-reviewed study