Melanotan 2

Reviewed August 22, 2026 · Artemis Labs

What is Melanotan-II?

Melanotan-II (MT-II) is a 7-residue cyclic heptapeptide (Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH₂, cyclized via Asp-Lys lactam bridge; molecular formula C₅₀H₆₉N₁₅O₉; MW 1024.18 Da; CAS 121062-08-6; ChEMBL CHEMBL1822; PubChem CID 5024411; Wikidata Q1881587). It is derived from the active core of alpha-melanocyte-stimulating hormone (alpha-MSH) and acts as a non-selective agonist at MC1R, MC3R, MC4R, and MC5R melanocortin G-protein-coupled receptors. The class distinguishes MT-II from the MC3R/MC4R-selective cyclic alpha-MSH(4-10) analog bremelanotide (PT-141), and from the linear 13-amino-acid alpha-MSH analog afamelanotide (Scenesse®).

Is Melanotan-II the same thing as afamelanotide / Scenesse®?

Melanotan-II is NOT afamelanotide / Scenesse®. Afamelanotide (Scenesse®, Clinuvel Pharmaceuticals) is a linear 13-amino-acid alpha-MSH analog FDA-approved in October 2019 for adult erythropoietic protoporphyria. Afamelanotide is structurally distinct from MT-II (different sequence, different length, different cyclization) and has a different regulatory status. Artemis Labs does NOT market, NOT substitute for, and NOT reference clinical indications of afamelanotide or Scenesse®. Our MT-II is a research-grade lyophilized peptide for in vitro and IACUC-approved animal research only. Several U.S. state Boards of Pharmacy have issued advisories against compounding melanotan products for cosmetic use; Artemis Labs PT-141, MT-II, and the broader research catalog are supplied strictly as research reagents – not as compounded pharmaceuticals and not as tanning, cosmetic, or self-administered preparations.

How do the two alpha-MSH-analog compounds compare?

What has Melanotan-II research reported since 2025?

• Adverse-event documentation – Resnick et al. 2026 (PMID 41890775): tanning-biology review explicitly documents unregulated Melanotan I/II adverse events including rhabdomyolysis, renal infarction, and priapism. Cited by Artemis as a primary reason for the research-only positioning.
• Persistent gingival pigmentation case report – Bonchev 2026 (PMID 41752902): brown maxillary and mandibular gingival pigmentation following self-administered MT-II injections, persisting at least 3 months after discontinuation. Cited as a documented adverse-event signal.
• Public-health signal – Sidhu et al. 2026 (PMID 41559011): social-media-driven unregulated MT-II misuse linked to ‘looksmaxxing’ and body-image culture as an emerging dermatologic and public-health risk.
• Class-level stability mapping – Chawathe & Sharma 2026 (PMID 41547183): LC-HRMS analytical framework mapping 14 distinct degradation products of afamelanotide under acidic, basic, neutral, oxidative, UV, and thermal stress. Directly applicable to MT-II’s purity verification as alpha-MSH-class context.
• Sustained-release alpha-MSH-class delivery – Anderson et al. 2026 (PMID 41999898): stereocomplexed beta-strand/hairpin hydrogel releasing alpha-MSH-analog peptide over months. Class-level PK innovation cited as alpha-MSH-class context only – not as an MT-II use recommendation.

How does Artemis Labs verify Melanotan-II purity and identity?

Each lot is supplied as a sterile lyophilised peptide powder, analytically verified by reverse-phase HPLC to ≥99% peptide purity, with identity confirmed by mass spectrometry. The compound shipped is the canonical 7-mer cyclic Ac-Nle-Asp-His-D-Phe-Arg-Trp-Lys-NH₂ sequence with Asp-Lys lactam closure. A third-party Certificate of Analysis with HPLC chromatogram, MS identity, residual-solvent assay, and endotoxin testing is available on request. The 2026 Chawathe & Sharma LC-HRMS degradation map (PMID 41547183) is the relevant alpha-MSH-class analytical reference for ongoing purity verification work.

What does the Melanotan-II evidence not show?

(1) Documented adverse-event signal from unregulated use. The 2026 dermatology literature (PMID 41890775, PMID 41752902, PMID 41559011) documents rhabdomyolysis, renal infarction, priapism, persistent gingival pigmentation, and social-media-driven misuse. These findings strengthen the case for research-only positioning. (2) Mechanistically related to but not equivalent to afamelanotide. Both are alpha-MSH analogs but they are different molecules (cyclic vs linear; 7-aa vs 13-aa; non-selective vs the afamelanotide profile). Afamelanotide clinical findings do not transfer to MT-II positioning. (3) Not FDA-approved in any formulation. Several U.S. state Boards of Pharmacy have issued compounding advisories. (4) Non-selective receptor profile creates broad systemic effects. Compared with MC3R/MC4R-selective bremelanotide (PT-141), MT-II’s non-selective activation across MC1R-MC5R produces a broader effect profile that is studied in the preclinical literature as a feature of the compound class, not as a clinical advantage.

How does Melanotan-II differ from PT-141 and oxytocin?

Unlike PT-141 (selective MC3R/MC4R cyclic alpha-MSH(4-10) analog with FDA-approved active ingredient in the Vyleesi® product), MT-II is non-selective across MC1R-MC5R and is not FDA-approved in any formulation. Unlike oxytocin (9-aa cyclic OXTR-agonist neuropeptide), MT-II acts through the broader melanocortin receptor family. The 2024 Inozemtseva et al. (PMID 39442746) paper directly compared MT-II vs Semax antidepressant/antistress effects in chronic stress models – see Semax for the mechanism-comparator citation.

What is the regulatory status of Melanotan-II?

Melanotan-II is NOT FDA-approved, NOT EMA-approved, and NOT DEA-scheduled. Afamelanotide / Scenesse® (a different molecule) is FDA-approved for adult erythropoietic protoporphyria – this approval does not transfer to MT-II. Several U.S. state Boards of Pharmacy have issued advisories against compounded melanotan products for cosmetic use. MT-II is not on the WADA Prohibited List 2026. Artemis Labs does NOT market Melanotan-II as a tanning agent, cosmetic, sexual-enhancement product, or self-administered preparation. Research-use-only framing applies to all Artemis Labs commercial supply. These statements have not been evaluated by the FDA. Not for human consumption, therapeutic use, or veterinary use.

Analytical Specifications

Methodology: every lot is verified by third-party reverse-phase HPLC for purity and by mass spectrometry for identity; the batch-specific Certificate of Analysis is available on request with every order.

References

1. Minder AE, Barman-Aksoezen J (2025). JAAD Case Reports. PMID 41542313
2. Chawathe A, Sharma N (2026). J Pharm Biomed Anal. PMID 41547183
3. Sidhu AS et al. (2026). Int J Dermatol. PMID 41559011
4. Peshin S et al. (2026). Reports (MDPI). PMID 41718315
5. Bonchev A (2026). Life (Basel). PMID 41752902
6. Shetty N et al. (2026). Photochem Photobiol. PMID 41766687
7. Seidl-Philipp M et al. (2026). J Dtsch Dermatol Ges. PMID 41793078
8. Barman-Aksoezen J et al. (2026). Expert Opin Pharmacother. PMID 41885813
9. Resnick G et al. (2026). J Clin Aesthet Dermatol. PMID 41890775
10. Anderson CF, Wang X, Schneider JP (2026). J Control Release. PMID 41999898
11. Inozemtseva LS et al. (2024). Comparison of MT-II and Semax antidepressant / antistress effects in chronic stress models. PMID 39442746

Science & Research

How does Melanotan-II act across the melanocortin receptors?

Melanotan-II is an alpha-MSH-derived cyclic heptapeptide that activates the melanocortin G-protein-coupled receptors MC1R, MC3R, MC4R, and MC5R non-selectively. MC1R activation on melanocytes drives eumelanin synthesis; MC3R/MC4R activation occurs across CNS reward and arousal circuitry; MC5R is expressed across exocrine and immune tissues. The non-selective receptor profile distinguishes MT-II from the MC3R/MC4R-selective bremelanotide (PT-141) and from the linear afamelanotide.

What did 2025-2026 research refine?

• Adverse-event documentation – Resnick et al. 2026 (PMID 41890775; in J Clin Aesthet Dermatol): tanning-biology review explicitly documents unregulated Melanotan I/II adverse events including rhabdomyolysis, renal infarction, and priapism.
• Persistent gingival pigmentation – Bonchev 2026 (PMID 41752902; in Life (Basel)): case report of brown maxillary and mandibular gingival pigmentation following self-administered MT-II injections; mucosal pigmentation persisted at least 3 months after discontinuation.
• Public-health and dermatology signal – Sidhu et al. 2026 (PMID 41559011; in Int J Dermatol): social-media-driven unregulated melanotan use linked to ‘looksmaxxing’ culture and body-dysmorphic-disorder overlap.
• alpha-MSH-class stability landscape – Chawathe & Sharma 2026 (PMID 41547183; in J Pharm Biomed Anal): LC-HRMS framework mapping 14 distinct degradation products of afamelanotide under acidic, basic, neutral, oxidative, UV, and thermal stress. Cited as alpha-MSH-class analytical context relevant to MT-II purity verification.
• Sustained-release alpha-MSH-class delivery – Anderson et al. 2026 (PMID 41999898; in J Control Release): stereocomplexed beta-strand/hairpin hydrogel platform releasing alpha-MSH-analog peptide over months. Class-level PK innovation, cited as alpha-MSH-class context only.
• Afamelanotide-class context – Seidl-Philipp et al. 2026 (PMID 41793078; Austrian EPP real-world QoL data) + Barman-Aksoezen et al. 2026 (PMID 41885813; emerging EPP pharmacotherapies review) + Peshin et al. 2026 (PMID 41718315; CEP case) + Minder & Barman-Aksoezen 2025 (PMID 41542313; first pediatric afamelanotide case) – these are afamelanotide findings, cited here as alpha-MSH-class context only. They do NOT transfer to MT-II positioning.
• EPP combination context – Shetty et al. 2026 (PMID 41766687; in Photochem Photobiol): Polypodium leucotomos extract adjunct to afamelanotide implants in EPP. Afamelanotide-class context only.

Entity Disambiguation

Quality and Specifications

• Purity: ≥99% by RP-HPLC; identity confirmed by mass spectrometry
• Form: Lyophilised white powder, 10 mg/vial
• Storage: Lyophilised ≤ -20°C, desiccated, protected from light
• Documentation: Batch-specific Certificate of Analysis with HPLC chromatogram, MS identity, residual-solvent assay, and endotoxin testing available on request

What does the Melanotan-II evidence not show?

• Documented adverse-event signal from unregulated use – rhabdomyolysis, renal infarction, priapism, persistent gingival pigmentation, social-media-driven misuse (Resnick 2026, Bonchev 2026, Sidhu 2026).
• Not FDA-approved in any formulation – several U.S. state Boards of Pharmacy have issued compounding advisories.
• Mechanistically related to but distinct from afamelanotide / Scenesse® – afamelanotide clinical findings do not transfer to MT-II positioning.
• Non-selective receptor profile creates broader systemic effects than the MC3R/MC4R-selective bremelanotide (PT-141).
• NOT a tanning agent, cosmetic, or self-administered preparation – Artemis Labs supplies MT-II strictly as a research reference compound.

References (10 PubMed-Verified, Scout 3 2026-05-20)

1. Minder AE, Barman-Aksoezen J (2025). JAAD Case Reports. PMID 41542313
2. Chawathe A, Sharma N (2026). J Pharm Biomed Anal. PMID 41547183
3. Sidhu AS et al. (2026). Int J Dermatol. PMID 41559011
4. Peshin S et al. (2026). Reports (MDPI). PMID 41718315
5. Bonchev A (2026). Life (Basel). PMID 41752902
6. Shetty N et al. (2026). Photochem Photobiol. PMID 41766687
7. Seidl-Philipp M et al. (2026). J Dtsch Dermatol Ges. PMID 41793078
8. Barman-Aksoezen J et al. (2026). Expert Opin Pharmacother. PMID 41885813
9. Resnick G et al. (2026). J Clin Aesthet Dermatol. PMID 41890775
10. Anderson CF, Wang X, Schneider JP (2026). J Control Release. PMID 41999898

Research Pairings

Pairing rationale below is mechanistic only. No dosing, frequency, duration, or human-use guidance is provided. Researchers design their own studies against their own institutional review, not against vendor copy. Artemis Labs does NOT market Melanotan-II for combined use as a tanning, cosmetic, or self-administered regimen.

Why is Melanotan-II studied alongside PT-141?

Receptor-selectivity comparison only: MT-II is non-selective across MC1R-MC5R; PT-141 is MC3R/MC4R-selective. Useful research-model pairing for dissecting selective vs broad melanocortin agonism within the same alpha-MSH-derived compound family. Not an Artemis-recommended combination.

Why is Melanotan-II studied alongside oxytocin?

Orthogonal receptor systems: MT-II acts across MC1R-MC5R; oxytocin acts on OXTR. Both are CNS-acting peptides studied within neuropeptide research contexts but on different receptor families. Useful research-model pairing for dissecting melanocortin-axis vs OXTR effects.

Why is Melanotan-II studied alongside Semax?

The 2024 Inozemtseva et al. (PMID 39442746) paper directly compared MT-II vs Semax antidepressant/antistress effects in chronic stress models – a mechanism-comparator citation. Useful research-model pairing within the broader alpha-MSH / ACTH-derived neuropeptide family.

Why is Melanotan-II studied alongside VIP?

Vasoactive-intestinal-peptide × non-selective melanocortin-agonist pairing studied in autonomic and vascular research models. Different receptor systems with convergent neuromodulatory effects across published research designs.

What related compounds does Artemis Labs list?

For melanocortin-family research see PT-141. For OXTR-axis research see Oxytocin. For autonomic / vascular research counterparts see VIP. For ACTH-derived neuropeptide research see Semax and Selank.