Compounds / Melanotan 2
Melanotan 2
Also known as: Melanotan II; MT-II; MT2; Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2; CAS 121062-08-6
Primary research focus: Melanocortin research (skin pigmentation, sexual function, appetite); not approved for human use
Last updated July 2026 · Reviewed against FDA labeling and published research.
What is Melanotan 2?
Melanotan 2 (MT-II) is a synthetic cyclic analog of alpha-melanocyte-stimulating hormone that activates melanocortin receptors non-selectively. Unlike Melanotan 1 (afamelanotide), which is FDA-approved for a rare disease, Melanotan 2 has no approved indication in any jurisdiction and has never completed a Phase 3 trial. It is widely sold on the gray market for tanning, and its use is associated with documented serious adverse events and active regulatory enforcement.
Melanotan 2 is a non-selective melanocortin receptor agonist, binding MC1R, MC3R, MC4R, and MC5R. MC1R activation on melanocytes stimulates eumelanin production, causing tanning without UV exposure. MC4R activation in the central nervous system produces erections and suppresses appetite, which is why the compound has effects far beyond pigmentation; this same non-selectivity underlies its side-effect profile. Its cyclic structure gives it high potency and metabolic stability relative to native alpha-MSH. A related MC4R-selective analog, bremelanotide (PT-141), was developed from this chemistry and is FDA-approved for a specific sexual-desire indication.
How it’s supplied
Not an FDA-approved or legally marketed medicine anywhere. It is sold on the gray market as a research-grade lyophilized powder for reconstitution and, in some channels, as nasal sprays. Independent testing has found substantial content variability: one analysis of vials labeled 10 mg found actual peptide content ranging from approximately 4.3 to 8.8 mg, and a 2022 study of online distributors found inconsistent purity and labeling.
Dosage Chart
Units shown are for a U-100 insulin syringe (100 units = 1 mL), calculated from the vial size and BAC water you select. Always confirm against your prescription and your syringe markings.
| Phase | Dose | Frequency | Notes |
|---|---|---|---|
| Week 1 | 250mcg | 1x Daily | — |
| Week 2 | 500mcg | 1x Daily | — |
| Week 3 | 750mcg | 1x Daily | — |
| Weeks 4-8 | 1mg | 1x Daily | — |
| Week 9+ | 1mg | 1x Weekly | — |
- Rotate injection sites to reduce irritation and lipohypertrophy
- Not for use during pregnancy or breastfeeding
- Do not exceed the recommended dose to try to speed results
Potential Benefits and Side Effects
Effects reported in published research. Not a promise of results, and not medical advice.
- Reported in very small human studies and gray-market use; no approved indication and no completed efficacy trial.
- Skin tanning (eumelanin production) without ultraviolet exposure, via MC1R.
- Erection induction via central MC4R activation.
- Appetite suppression via central MC4R activation.
- These effects are documented but must be weighed against a substantial and well-documented harm profile.
- Common in small trials and reported use: nausea, vomiting, facial flushing, yawning and stretching, and decreased appetite.
- Dermatologic: darkening of existing moles, eruptive and atypical melanocytic nevi, uneven or excessive pigmentation.
- Serious events reported in the case literature: melanoma and melanoma in situ, ischemic priapism (sometimes requiring surgery), rhabdomyolysis with renal dysfunction, renal infarction, and posterior reversible encephalopathy syndrome.
- Hypertension has also been reported.
- Product-quality variability compounds dosing risk.
Warnings and contraindications
Important safety information. This is not exhaustive — read the full prescribing information and consult your prescriber or pharmacist.
- No FDA-approved labeling exists; the following reflect published case reports, regulator warnings, and the compound's status.
- Published case reports link Melanotan 2 use to melanoma, eruptive and atypical melanocytic nevi, darkening of existing moles, ischemic priapism (in at least one case requiring surgery), rhabdomyolysis, renal infarction, and posterior reversible encephalopathy syndrome (PRES).
- Causality for melanoma has not been established in a controlled study, and reviews note confounding by sun-seeking behavior, but the mechanistic concern and case literature are substantial.
- No completed human safety or efficacy trial has been published; the total published trial exposure is very small.
- Gray-market product content varies widely from label, compounding dosing risk.
- Regulators have acted against it: the UK MHRA issued public warnings, the FDA has issued warning letters and maintains an import alert, and Australia reclassified it to Schedule 9 in February 2026, where possession without a research licence carries criminal penalties.
- People with a personal or family history of melanoma or dysplastic nevi, cardiovascular, renal, or neurological disease, or predisposition to priapism are at particular concern.
- Not established as a drug; no FDA labeling. Precautionary considerations based on the case literature and mechanism include personal or family history of melanoma, dysplastic nevus or FAMMM syndrome, active cardiovascular, renal, or neurological disease, predisposition to priapism or vascular thrombosis, pregnancy or breastfeeding, and known hypersensitivity.
Reconstitution Steps
How to prepare the lyophilized vial. Confirm specifics with your pharmacist or prescriber.
- Confirm the amount of peptide in the vial and the volume of diluent you intend to use before starting.
- Wash your hands and gather supplies: the lyophilized vial, the diluent (typically bacteriostatic water), an alcohol swab, and a sterile syringe.
- Let the vial and diluent reach room temperature if they were refrigerated or frozen.
- Wipe the rubber stopper of both the peptide vial and the diluent vial with a fresh alcohol swab and let them air dry.
- Draw the intended diluent volume into the syringe.
- Insert the needle into the vial and slowly release the diluent down the inside wall rather than directly onto the powder, to avoid foaming.
- Do not shake. Gently swirl or roll the vial until fully dissolved.
- Inspect the solution: it should be clear and colorless with no visible particles. Do not use if cloudy or containing particles.
- Note the resulting concentration (amount divided by diluent volume) so it matches the reconstitution calculator on this page.
- Label the vial with the reconstitution date and store as directed under reconstituted storage.
US regulatory status
Classifications are public record but can change. For reference only, not legal advice.
Development: Melanotan 2 originated from melanocortin research at the University of Arizona in the 1980s and 1990s; a pilot Phase 1 study (Dorr et al., Life Sciences 1996) evaluated it as a superpotent cyclic melanotropic peptide, and a 1998 study by Wessells and colleagues examined erectile effects. Total published human trial exposure is very small (on the order of tens of participants), with transient nausea, flushing, yawning, and decreased appetite as the reported dose-limiting effects. Development of MT-II itself was abandoned; the MC4R-selective derivative bremelanotide (PT-141) was advanced instead and received FDA approval in 2019 for hypoactive sexual desire disorder in premenopausal women. Melanotan 2 has never been approved anywhere. Enforcement history includes the 2016 conviction and FDA debarment of a US distributor. In the September 2023 FDA action it was placed in Category 2, and it is expected to remain restricted in the 2026 reclassification.
Notes: Melanotan 2 is not FDA-approved and has never received regulatory approval in any jurisdiction. In the US it was placed in FDA Category 2 in September 2023 (barring compounding) and is expected to remain restricted rather than return to Category 1 in the 2026 reclassification; verify against the current FDA list. Products sold as MT-2 are unapproved new drugs; the FDA has issued warning letters and maintains Import Alert 66-41 permitting border detention without physical examination. The UK MHRA has warned consumers and vendors, and Australia moved it to Schedule 9 in February 2026, where possession without a research licence is a criminal matter. It is not a federally controlled substance in the US. (Status current as of mid-2026.)
International status
Pharmacokinetics
Storage and handling
Important Notes
Practical considerations for consistency and safety.
- Melanotan 2 is NOT the same as Melanotan 1 (afamelanotide/Scenesse); Melanotan 1 is FDA-approved for a rare disease, Melanotan 2 is approved nowhere.
- Its non-selectivity (MC1R, MC3R, MC4R, MC5R) is why it causes erections, nausea, and appetite suppression alongside tanning.
- Published case reports link it to melanoma, priapism, rhabdomyolysis, renal infarction, and PRES; causality for melanoma is unproven but the concern is mechanistically plausible.
- Gray-market vials have been shown to contain substantially less peptide than labeled.
- Enforcement is active: FDA import alert and warning letters, MHRA warnings, and Australian Schedule 9 classification (criminal penalties).
Lifestyle Factors
- Any pigmentary change warrants dermatologic surveillance; new or changing moles should be evaluated.
- It does not remove the need for sun protection, and reported increases in melanoma rates among users may partly reflect concurrent sun-seeking behavior.
References
Related compounds
Important disclaimer
This page is an educational reference, not medical advice, a diagnosis, or a treatment recommendation, and not a substitute for your prescriber or pharmacist. Approval and regulatory status varies by compound and can change. Always confirm against current prescribing information and consult a qualified healthcare professional before making any decision about a medication.