Melanotan II: evidence, dosing, safety & interactions
Melanotan-II (MT-II), a synthetic alpha-MSH analogue
This is a lab-made hormone shot that darkens your skin without sun exposure. It's not approved as a medicine anywhere, and it comes with real reported side effects, including nausea and dangerous prolonged erections.
- What it is
- A synthetic hormone analogue injected to stimulate melanin production and tan the skin, sold without any approved medical indication.
- Evidence
- No completed controlled human efficacy trial exists. What is published are case reports of harm: a confirmed malignant melanoma diagnosis, new atypical moles after injection, and priapism requiring hospital treatment.
- Studied dose
- No standardised or approved human dose exists. Doses sold online are unregulated and vary by supplier.
- Safety
- Documented case reports include a confirmed malignant melanoma diagnosis, new or changing moles with dysplastic features, and acute priapism requiring surgical decompression after injection.
What human trials actually show
Randomized, placebo-controlled human trials only. Animal data never appears in this section — it cannot raise a grade, and it is noted separately below.
- 01International Journal of Oral and Maxillofacial Surgery2025— Malignant melanoma following Melanotan II nasal spray use
- Design
- Case report
- Dose
- Melanotan II nasal spray, self-administered for tanning
- Duration
- Presented with an anterior maxillary mass; diagnosed after biopsy
1 patient, a 22-year-old woman
The patient developed a mass in the anterior maxilla after using Melanotan II nasal spray for tanning. Histological analysis confirmed mucosal malignant melanoma, requiring surgical resection and ongoing immunotherapy. The authors reviewed the wider literature on a possible association between Melanotan use and melanoma and flagged the need for clinical awareness of this serious potential harm.
doi:10.1016/j.ijom.2025.03.014 - 02Sexual Medicine2021— Priapism following Melanotan II injection
- Design
- Case report
- Dose
- Subcutaneous injection of Melanotan II, self-administered
- Duration
- Acute presentation requiring emergency management
1 patient
The patient presented with acute ischemic priapism after subcutaneous Melanotan II injection. Standard first-line treatment (cavernosal aspiration, irrigation, and intracavernous phenylephrine) failed to resolve it, and the patient required surgical penoscrotal decompression. The authors noted this was only the third such case reported in the literature at the time.
doi:10.1016/j.esxm.2020.100298 - 03BMJ Case Reports2019— Priapism following Melanotan injection
- Design
- Case report
- Dose
- Abdominal subcutaneous injection of melanotan, self-administered
- Duration
- Acute presentation; erectile function not yet recovered at 4-week follow-up
1 patient
The patient developed acute low-flow priapism after injecting melanotan, managed with cavernosal aspiration and irrigation without needing surgery, but had not recovered erectile function by 4 weeks. The authors describe priapism as an unreported side effect of melanocortin analogue use that should be considered in any future clinical application.
doi:10.1136/bcr-2018-227644
There is no completed controlled human trial establishing Melanotan II's efficacy or safety for tanning, libido, or erectile function in the way it is marketed. The published human literature is almost entirely case reports of adverse events rather than trials of benefit — which is itself informative: a compound with a real efficacy trial behind it would have that trial cited by sellers, and none exists. The case reports available describe genuinely serious outcomes — a confirmed malignant melanoma diagnosis, dysplastic mole formation, and priapism requiring hospital-level intervention — in a small number of documented patients; because there is no systematic surveillance or registry of Melanotan II users, nobody knows how common these events actually are, only that they occur and have been serious enough to be published, including in a case that required cancer surgery and immunotherapy.
Grade D — insufficient or unsafe. No health authority has approved Melanotan II for any use, and there is no controlled human efficacy trial behind it — it was developed as a research compound and never completed drug development. On top of that absence of evidence, published case reports document specific, real harms, including a confirmed diagnosis of malignant melanoma after use, new and changing moles, and priapism requiring emergency urological intervention. This is a case of both insufficient evidence and demonstrated risk. How we grade evidence.
Side effects & safety
- Skin, mole and melanoma risk
- A 2025 case report documented a confirmed diagnosis of malignant melanoma of the oral mucosa in a young woman after using Melanotan II nasal spray, requiring surgical resection and immunotherapy. Separate case reports document new-onset atypical (dysplastic) moles appearing within days of injection, and darkening of existing moles. Dermatologists advise against use in anyone with a personal or family history of melanoma.
- Priapism
- Multiple published case reports describe acute, prolonged, painful erections requiring emergency urological treatment after injection, in at least one case requiring surgery and leaving erectile function not fully recovered at follow-up.
- Commonly reported but less severe
- Nausea, flushing, and appetite suppression are widely reported with melanocortin-receptor agonists as a drug class, consistent with mechanism, though systematic data specific to Melanotan II are limited to case series rather than trials.
- Product risk
- No approved pharmaceutical-grade formulation exists. Products sold online as Melanotan II vary in purity, concentration and sterility, which is a risk independent of the peptide's own biological effects.
- The honest caveat
- This is not a peptide where the main problem is a lack of evidence — the main problem is that the evidence which does exist is case reports of real harm, in a compound sold for a purely cosmetic effect achievable by other means.
Interactions with medications
The section most longevity sites skip. If you take prescription medication, read this before anything else on the page.
Case reports directly document new dysplastic moles after Melanotan injection. Anyone with a melanoma risk factor is using a melanocyte-stimulating drug against the direction that risk factor points.
Melanotan II acts on pathways involved in erectile physiology and has been linked to priapism on its own. Combining it with erectile-dysfunction medications or antihypertensives has not been studied and adds an unstudied, plausible interaction on top of an already-documented single-agent risk.
No controlled human interaction data exist for Melanotan II with any other drug class.
Is Melanotan II legal where you live?
Regulatory status is tracked per market and reviewed on the date shown. Where a compound is not authorised, this site does not link to sellers.
Not an approved drug for any use and not lawfully sold as a dietary supplement. The FDA has not evaluated Melanotan II for safety or effectiveness for tanning or any other indication.
Source: US Food and Drug Administration
The UK explicitly banned the sale, supply and possession of Melanotan I and II in 2019. The MHRA classifies it as an unlicensed medicine with unestablished safety.
Source: MHRA
No EU marketing authorisation exists for Melanotan II as a medicine, and it is not permitted as a food supplement or cosmetic.
Source: European Medicines Agency
Aucune autorisation de mise sur le marché n'existe pour le Melanotan II en tant que médicament, et il n'est autorisé ni comme complément alimentaire ni comme cosmétique.
Source: European Medicines Agency
No existe autorización de comercialización para la Melanotan II como medicamento, y no está permitida como complemento alimenticio ni cosmético.
Source: European Medicines Agency
Es besteht keine Zulassung für Melanotan II als Arzneimittel, weder als Nahrungsergänzungsmittel noch als Kosmetikum.
Source: BfArM / European Medicines Agency
Not an approved medicine and not sold as a supplement in the UAE. We found no verified MOHAP-published position specific to Melanotan II, but no legitimate consumer or over-the-counter route to the compound was found.
Source: UAE Ministry of Health and Prevention (MOHAP)
Not SFDA-registered in any category. We could not independently verify a specific SFDA-published position on Melanotan II, but no legitimate consumer or clinical route to the compound was found.
Source: Saudi Food and Drug Authority (SFDA)
Non è un farmaco autorizzato né un integratore alimentare o cosmetico consentito. La vendita al di fuori dei canali autorizzati può inoltre rientrare nelle sanzioni della Legge 376/2000 per gli sportivi tesserati, data la classificazione WADA come sostanza non approvata (categoria S0).
Source: Ministero della Salute / Legge 376/2000 antidoping
Melanotan II is niet goedgekeurd als geneesmiddel, voedingssupplement of cosmeticum in Nederland of de EU. Toediening aan mensen blijft niet goedgekeurd en niet zonder risico.
Source: CBG-MEB / IGJ (Geneesmiddelenwet)
Segundo reportagens sobre alertas da Anvisa a respeito de peptídeos vendidos online, a Melanotan está entre os compostos amplamente divulgados sem registro em nenhuma categoria regulatória. Não conseguimos verificar de forma independente um documento primário da Anvisa citando a Melanotan II especificamente pelo nome, mas nenhuma via legal de comercialização para uso humano foi encontrada.
Source: Agência Nacional de Vigilância Sanitária (ANVISA)
Dosing & timing
No health authority has approved a dose of Melanotan II for any indication. There is no pharmaceutical-grade reference product.
Vials and "loading" or "maintenance" protocols sold online are set by sellers, not by any clinical trial, and purity and concentration are not independently verified.
The documented case reports of both mole changes and priapism followed self-administered subcutaneous injection — the same route the product is marketed and sold for.
Questions people actually ask
Is Melanotan II safe?
No health authority has approved it, and the published human literature includes case reports of specific, serious harms: a confirmed malignant melanoma diagnosis, new dysplastic moles, and priapism serious enough to require emergency urological treatment. That is a documented risk profile, not just an absence of safety data.
Does Melanotan II actually tan the skin?
It stimulates melanin production through the same receptor pathway as natural tanning hormones, which is mechanistically why it darkens skin — but this effect has never been established through an approved clinical trial, and it comes with the documented mole and priapism risks described in the case-report literature.
Is Melanotan II legal?
It is not an approved medicine or lawfully sold supplement anywhere covered on this site. The UK explicitly banned the sale, supply and possession of Melanotan I and II in 2019, and it is captured by World Anti-Doping Agency prohibitions in competitive sport as a non-approved substance.
Can Melanotan II cause moles or skin cancer?
Yes — a published 2025 case report documents a confirmed diagnosis of malignant melanoma of the oral mucosa in a patient who used Melanotan II nasal spray, requiring surgery and immunotherapy. Other case reports document new, atypical (dysplastic) moles appearing within days of injection. Anyone with a personal or family melanoma history should treat this as a specific, documented reason to avoid it.
Is priapism a real risk with Melanotan II?
Yes — it is documented in multiple published case reports, including at least one requiring surgical decompression and one where erectile function had not fully recovered at follow-up. It is described in the literature as a rare but serious and likely underreported complication.