Melanotan 2
Published research and evidence base
Melanotan II and afamelanotide are synthetic analogues of alpha-melanocyte-stimulating hormone that act at melanocortin receptors to increase eumelanin synthesis. Afamelanotide (a selective, largely MC1R-directed analogue) is an approved medicine for erythropoietic protoporphyria supported by randomised placebo-controlled trials and post-authorisation safety cohorts, and has been trialled with narrowband UV-B in vitiligo. Melanotan II is a non-selective, unlicensed peptide sold illegally for tanning; it has never been through a completed efficacy or safety programme, and its published human literature consists almost entirely of adverse-event case reports, including eruptive and dysplastic naevi, melanoma and mucosal melanoma, priapism, renal infarction and systemic reactions.
- Studies cited
- 20
- Published 2023+
- 12
- Newest paper
- 2026
- Last reviewed
- Aug 2026
Recurring themes in the literature
- melanocortin 1 receptor agonism
- eumelanin induction and photoprotection
- erythropoietic protoporphyria phototoxicity
- vitiligo repigmentation
- eruptive and dysplastic melanocytic naevi
- melanoma case reports
- unregulated peptide supply and social media promotion
- non-selective melanocortin receptor adverse effects
Compound identifiers
- CAS
- 121062-08-6
- PubChem
- 92432
What Melanotan 2 is, chemically.
- Molecular formula
- C50H69N15O9
- Molecular weight
- 1024.2 g/mol
- CAS number
- 121062-08-6
- PubChem CID
- 92432
Melanotan II
These figures come from the PubChem record for this compound and describe the free base. Lyophilised peptide is normally supplied as an acetate or trifluoroacetate salt and carries residual water, so the mass of powder in a vial is not the same quantity as the molecular weight above would suggest. Chromatographic purity on a certificate of analysis does not resolve that difference either — how to read a certificate of analysis explains why.
20 published studies.
Ordered by strength of study design, then by recency. Every entry links to its source record so the finding can be checked against the paper rather than taken on our word.
- 01Systematic review2026
Insights into Tanning Biology and Tanning Products.
Resnick G, et al. · The Journal of Clinical and Aesthetic Dermatology · PRISMA systematic review of 68 peer-reviewed studies on dihydroxyacetone, melanotan, forskolin and carotenoids
The review assessed mechanisms, clinical uses, formulations and adverse effects of self-tanning agents, covering melanotan alongside dihydroxyacetone, forskolin and carotenoids. It is the most recent systematic appraisal placing melanotan within the tanning-product landscape.
Reported safety finding. Reviewed adverse effects of unregulated tanning agents including melanotan.
- 02Systematic review2024
A systematic review of case series and clinical trials investigating systemic oral or injectable therapies for the treatment of vitiligo.
Jafarzadeh A, et al. · Skin Research and Technology · systematic review of case series and clinical trials of systemic oral and injectable vitiligo therapies
The review placed afamelanotide among systemic injectable options for vitiligo alongside corticosteroids, immunosuppressants and other agents, and characterised the overall evidence base for systemic vitiligo therapy as limited and heterogeneous.
- 03Human clinical2026
Afamelanotide improves quality of life and light tolerance in Austrian erythropoietic protoporphyria patients.
Seidl-Philipp M, et al. · Journal der Deutschen Dermatologischen Gesellschaft · Austrian erythropoietic protoporphyria patient cohort treated with afamelanotide
Afamelanotide treatment was associated with improved quality of life and light tolerance in an Austrian EPP cohort, adding a further national real-world dataset to the approved indication.
- 04Human clinical2025
German Cohort Observational Study to Investigate the Short- and Long-Term Safety and Clinical Effectiveness of Afamelanotide 16 mg (SCENESSE) in Patients With Erythropoietic Protoporphyria (EPP).
Homey B, et al. · Photodermatology, Photoimmunology & Photomedicine · post-authorisation safety study (EUPAS13004), German arm of the European EPP Disease Registry, n=200 treated patients
This regulator-mandated observational study collected short- and long-term safety and effectiveness data on afamelanotide 16 mg in treated EPP patients. It represents the structured pharmacovigilance that exists for the approved analogue and has no counterpart for melanotan II.
- 05Human clinical2024
Afamelanotide for Treatment of the Protoporphyrias: Impact on Quality of Life and Laboratory Parameters in a US Cohort.
Leaf RK, et al. · Life (Basel) · US cohort of patients with protoporphyria treated with afamelanotide
The study examined quality-of-life change and laboratory parameters in US protoporphyria patients receiving afamelanotide, contributing observational rather than randomised evidence.
- 06Human clinical2023
Dersimelagon in Erythropoietic Protoporphyrias.
Balwani M, et al. · The New England Journal of Medicine · randomised placebo-controlled phase 2 trial, adults 18-75, placebo versus dersimelagon 100 mg or 300 mg once daily for 16 weeks
Dersimelagon, an orally administered selective MC1R agonist that increases skin eumelanin, was assessed for time to onset and severity of symptoms after sunlight exposure in erythropoietic and X-linked protoporphyria. The trial demonstrates that MC1R agonism is being developed as a regulated oral drug class distinct from injectable tanning peptides.
- 07Human clinical2020
Association of Afamelanotide With Improved Outcomes in Patients With Erythropoietic Protoporphyria in Clinical Practice.
Wensink D, et al. · JAMA Dermatology · single-centre prospective post-authorisation safety and efficacy cohort, EMA-approved protocol, June 2016 to September 2018
Afamelanotide treatment in routine practice was assessed for time spent outdoors, number of phototoxic reactions, disease-specific quality of life, use of protective clothing and adverse events. The study extended pivotal-trial findings into longer-term real-world follow-up.
- 08Human clinical2015
Afamelanotide for Erythropoietic Protoporphyria.
Langendonk JG, et al. · The New England Journal of Medicine · two multicentre randomised double-blind placebo-controlled trials of 16 mg subcutaneous implants; 74 patients (EU) and 94 patients (US)
Patients received afamelanotide or placebo implants every 60 days and were assessed on duration of sun exposure, number and severity of phototoxic reactions and quality of life. These are the pivotal trials underpinning regulatory approval of afamelanotide for erythropoietic protoporphyria.
- 09Human clinical2015
Afamelanotide and narrowband UV-B phototherapy for the treatment of vitiligo: a randomized multicenter trial.
Lim HW, et al. · JAMA Dermatology · randomised multicentre trial, n=55 adults with non-segmental vitiligo (15-50% BSA), afamelanotide 16 mg implant plus NB-UV-B (n=28) versus NB-UV-B alone (n=27)
Combination therapy with afamelanotide implants added to narrowband UV-B was compared with narrowband UV-B monotherapy in Fitzpatrick skin phototypes III to VI. This is the principal randomised evidence for a melanocortin analogue in vitiligo.
- 11Review2021
Melanotan II User Experience: A Qualitative Study of Online Discussion Forums.
Gilhooley E, et al. · Dermatology · retrospective qualitative analysis of UK and Ireland online chatrooms and forums, January 2016 to October 2017
The study characterised motivations for melanotan II use and self-reported side effects from user forums, and noted that the covert nature of supply makes population-level prevalence and adverse-event rates difficult to establish.
Reported safety finding. Self-reported side effects catalogued from user communities; true adverse-event incidence is unmeasurable because supply is unregulated.
- 12Review2017
Risks of unregulated use of alpha-melanocyte-stimulating hormone analogues: a review.
Habbema L, et al. · International Journal of Dermatology · narrative review of unregulated melanotan I and II use compared with approved afamelanotide
The review concluded that although afamelanotide has been thoroughly tested and deemed safe for its licensed indications, illegally supplied melanotans carry risks arising from unknown preparation, administration and dosage, and that case reports of adverse events following unregulated melanotan use were increasing.
Reported safety finding. Unregulated melanotan I and II preparations are of unknown purity, dose and sterility; a growing case-report literature documents dermatological and systemic harms.
- 13Case report2026
Five primary melanomas in situ in a patient with recent tanning bed use, melanotan exposure, and anabolic hormone use.
Vadner DJ, et al. · JAAD Case Reports · single patient with concurrent tanning bed use, melanotan exposure and anabolic hormone use
Five primary melanomas in situ were diagnosed in one patient with recent melanotan exposure alongside tanning bed and anabolic hormone use. Confounding by concurrent ultraviolet exposure means causality cannot be attributed to melanotan.
Reported safety finding. Multiple primary in situ melanomas reported in the context of melanotan exposure.
- 14Case report2026
Changes in Oral Mucosa Associated with Melanotan II Injections: A Case Report.
Bonchev A, et al. · Life (Basel) · three-month follow-up of a patient who self-administered melanotan II for 64 days
Brown, nearly symmetrical pigmentation appeared on the attached gingiva of both maxillary and mandibular arches, most intense anteriorly in the lower jaw. The report documents mucosal pigmentation as a consequence of unregulated self-injection.
Reported safety finding. Oral mucosal hyperpigmentation following self-administered melanotan II.
- 15Case report2026
Depigmented Facial and Neck Patches Following Melanotan Use in a Patient With Atopic Dermatitis and Alopecia Areata.
Ume A, et al. · Clinical and Experimental Dermatology · single patient with atopic dermatitis and alopecia areata
Depigmented facial and neck patches developed following melanotan use in a patient with pre-existing autoimmune and atopic disease. The report describes a pigmentary adverse outcome opposite to the intended effect.
Reported safety finding. Depigmentation reported after melanotan use in a patient with autoimmune comorbidity.
- 16Case report2025
Melanotan II nasal spray: a possible risk factor for oral mucosal malignant melanoma?
Yassin Alsabbagh A, et al. · International Journal of Oral and Maxillofacial Surgery · 22-year-old woman who used a melanotan II nasal spray for tanning
The patient developed an anterior maxillary mass histologically confirmed as mucosal malignant melanoma, treated by surgical resection followed by immunotherapy. The authors reviewed the literature on a possible association between melanotan use and melanoma and called for awareness of serious adverse effects of melanotan II nasal spray.
Reported safety finding. Oral mucosal malignant melanoma reported after melanotan II nasal spray use.
- 17Case report2025
Pyoderma Gangrenosum Secondary to Melanotan.
Dickson D, et al. · Cureus · single patient case report
Pyoderma gangrenosum was reported as a complication attributed to melanotan use, adding a non-pigmentary inflammatory dermatosis to the documented adverse-event profile of unregulated injectable tanning peptides.
Reported safety finding. Pyoderma gangrenosum attributed to melanotan.
- 18Case report2014
Melanoma associated with the use of melanotan-II.
Hjuler KF, Lorentzen HF · Dermatology · 20-year-old woman, Fitzpatrick skin type II, 3-4 week course of melanotan II self-injection with concurrent sunbed use
A suspicious gluteal melanocytic lesion excised three months after a course of melanotan II self-injection was histologically confirmed as cutaneous melanoma, with universally intense pigmentation of the surrounding skin. Concurrent sunbed use is an acknowledged confounder.
Reported safety finding. Cutaneous melanoma diagnosed in temporal association with melanotan II self-injection and sunbed use.
- 19Case report2012
Melanotan-associated melanoma in situ.
Ong S, Bowling J · Australasian Journal of Dermatology · single case of melanoma in situ in a melanotan user
The authors reported melanoma in situ associated with melanotan use and noted that injectable melanotropic peptides are unlicensed compounds with an unproven safety record sold over the internet, with prior reports of dysplastic naevi and melanoma.
Reported safety finding. Melanoma in situ associated with unlicensed melanotropic peptide use.
- 20Case report2009
Eruptive melanocytic naevi following melanotan injection.
Cousen P, et al. · British Journal of Dermatology · case report of eruptive melanocytic naevi after melanotan injection
This early report established the eruptive melanocytic naevus signal that has since been replicated in multiple independent case reports across several countries. The PubMed record carries no abstract.
Reported safety finding. Eruptive melanocytic naevi following melanotan injection; the index report for this adverse-event pattern.
What this evidence does not establish.
There are no completed randomised controlled trials of melanotan II for any indication, no pharmacovigilance system covering it, and no characterisation of the purity, dose or sterility of illicitly supplied product; the entire human melanotan II literature is case reports, letters and qualitative forum analyses. Because melanotan II is non-selective across melanocortin receptors, its systemic effects differ from those of the MC1R-selective approved analogues, so afamelanotide trial data cannot be used to infer melanotan II safety. Whether melanotan exposure causes melanoma is unresolved: reported cases are consistently confounded by concurrent ultraviolet and sunbed exposure, and no controlled epidemiological study exists.
Common questions about the research.
- What is Melanotan 2?
Melanotan 2 (MT-II) is a synthetic cyclic analogue of alpha-melanocyte-stimulating hormone, developed as a research tool for studying melanocortin-receptor pharmacology. It is a non-selective agonist at the MC1, MC3, MC4, and MC5 receptors.
- How does it differ from PT-141 (bremelanotide)?
PT-141 is a metabolite-derived analogue of Melanotan 2 developed for MC4R selectivity. MT-II activates the wider melanocortin receptor family, whereas the PT-141 programme deliberately narrowed the receptor profile after the erectile-response findings in the MT-II crossover study.
- Why is the research literature on this compound so small?
MT-II served mainly as a proof-of-concept tool compound. Once its receptor pharmacology was mapped, clinical development shifted to receptor-selective successors, so the direct MT-II literature consists of the original design papers and a handful of small early-phase trials.
Available from our catalog
For research purposes only. Not for human consumption, diagnosis, treatment, or prevention of any condition. Nothing on this page is medical advice, and no study summarised here should be read as a recommendation.