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Alpha-MSH: quick citable summary
Alpha-MSH is listed by PeptaHub as a skin & beauty peptide with a research only legal-status classification. The page summarizes mechanism, research context, common routes, safety notes, and references for writers and AI answer engines.
PeptaHub. “Alpha-MSH: Mechanism, Research Context, Safety.” peptahub.com, 2026. https://peptahub.com/peptides/alpha-msh. Licensed CC BY 4.0.
License: Creative Commons Attribution 4.0 International. Link back to https://peptahub.com/peptides/alpha-msh.
What is Alpha-MSH?
Alpha-MSH is an endogenous tridecapeptide driving skin pigmentation via MC1R with potent anti-inflammatory effects. Afamelanotide (Scenesse) is FDA-approved for erythropoietic protoporphyria.
Overview
Alpha-MSH (α-Melanocyte-Stimulating Hormone) is an endogenous tridecapeptide derived from POMC (pro-opiomelanocortin). It is a non-selective agonist at melanocortin receptors MC1R–MC5R, driving skin pigmentation via melanogenesis and exerting potent anti-inflammatory effects through central and peripheral pathways. Synthetic analogs include afamelanotide (melanotan I) and melanotan II.
Mechanism of action
α-MSH binds melanocortin receptors with highest affinity at MC1R, activating Gs-protein signaling and increasing intracellular cAMP. Published binding constants vary by assay and species, so no single figure is quoted here. At melanocytes, cAMP activates MITF transcription factor, upregulating tyrosinase and inducing melanin synthesis. At immune cells, α-MSH suppresses NF-κB activation, reducing pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) and promoting anti-inflammatory pathways. MC4R signaling in the hypothalamus mediates appetite suppression and energy homeostasis effects.
Reported study ranges
| Purpose | Route | Reported range | Frequency | Notes |
|---|---|---|---|---|
| anti-inflammatory research (animal) | subcutaneous | 50–500 mcg/kg | once or twice daily per protocol |
Reported ranges are for research context only. Consult a qualified healthcare professional before using any peptide.
Convert Alpha-MSH research-range units
Need to convert mg to mcg, dose volume, or U-100 syringe units? Use the peptide dose unit converter for educational calculation support.
Research summary
Extensive preclinical and clinical research demonstrates α-MSH's dual role in pigmentation and immunomodulation. Studies show significant anti-inflammatory effects in models of colitis, arthritis, and uveitis. The synthetic linear analog afamelanotide is FDA-approved for erythropoietic protoporphyria. Research also explores α-MSH in neuroprotection, ischemia-reperfusion injury, and fever regulation. Melanotan II (cyclic analog) has been widely studied for tanning and sexual function but is not approved for human use.[1][2][3][4][5]
Evidence grading
Each claimed benefit is graded by the strength of available evidence. Grades reflect study quality, not effect size.
Strong = multiple RCTs · Moderate = limited trials or observational · Preliminary = animal or in vitro only · Insufficient = anecdotal or no published data
Side effects
Side effects vary by individual. This is not an exhaustive list. Report unusual symptoms to a healthcare professional.
Common stacks
Peptides commonly paired with Alpha-MSH for synergistic effects.
Legal status
Endogenous α-MSH is available for laboratory research only. Synthetic analogs (melanotan I/II) are not approved for human use in the US. Afamelanotide (Scenesse) is FDA-approved for erythropoietic protoporphyria as a prescription drug.
Sourcing & access
Research compound
Alpha-MSH is classified as a research compound. Regulatory status varies by jurisdiction. Always verify current legal status and source from vendors providing third-party certificates of analysis (COA).
Frequently asked questions
Alpha-MSH (alpha-Melanocyte-Stimulating Hormone) is an endogenous tridecapeptide derived from POMC (pro-opiomelanocortin). It is a non-selective agonist at melanocortin receptors MC1R through MC5R, driving skin pigmentation and exerting potent anti-inflammatory effects through central and peripheral pathways.
Alpha-MSH binds MC1R with high affinity, activating Gs-protein signaling and increasing cAMP. At melanocytes, this activates MITF transcription factor and upregulates tyrosinase to induce melanin synthesis. At immune cells, it suppresses NF-kB activation and reduces pro-inflammatory cytokines. MC4R signaling mediates appetite suppression.
Alpha-MSH is a research compound with reported side effects including nausea, flushing, spontaneous erections (MC4R mediation), and hyperpigmentation with repeated dosing. The FDA-approved analog afamelanotide has a well-established clinical safety profile for its approved indication.
Melanotan II is a cyclic synthetic analog of alpha-MSH with broader receptor activity and greater metabolic stability. While alpha-MSH is the endogenous linear peptide with a short half-life of 10-20 minutes, melanotan II is a modified version studied for tanning and sexual function but not approved for human use.
Research references
- Melanocortin-4 receptor complexity in energy homeostasis, obesity and drug development strategiesReview
- Alpha-Melanocyte-Stimulating Hormone-Mediated Appetite Regulation in the Central Nervous SystemPubMed
- Structures of active melanocortin-4 receptor-Gs-protein complexes with NDP-alpha-MSH and setmelanotidePubMed
- The central melanocortin system as a treatment target for obesity and diabetes: A brief overviewReview
- Melanocortin receptor agonists suppress experimental autoimmune uveitisPubMed