Melanotan II
MT-II / Cyclic MSH Analog
Evidence grade 1 of 5, Untested. Read how the Atlas grades evidence.
Melanotan II is an unapproved cyclic alpha-MSH (melanocortin) analog with no completed clinical development and no marketing authorization in any major jurisdiction; its development as a medicine was halted for safety reasons. Human evidence is limited to small early pharmacology studies plus a growing case-report literature documenting harm, including rhabdomyolysis with acute kidney injury (Nelson 2012), renal infarction, priapism, and melanomas and changing/darkening moles arising in users. The documented-harm signal is stronger and better established than any evidence of benefit, so an honest grade is grade 1, foregrounding the harms.
Counted on the record: 5 human studies, 0 randomized trials, 1 animal study, 1 lab study.
No randomized controlled trial count is assigned beyond the approved zero. Other human totals remain unnormalized.
- FDA
- Not approved; FDA warning letter to Melanocorp (2007) and later felony conviction plus debarment of a supplier (Manookian, 2016)
- WADA
- Not on the WADA Prohibited List
Reference only. Not medical advice.
What can go wrong
Sold illegally as an unapproved injectable; documented harms include changing and darkening moles with melanoma case reports, rhabdomyolysis with acute kidney injury, renal infarction, priapism, and severe nausea, with unknown gray-market purity.
Talk to a clinician before taking this, particularly if you have any history of cancer. The Atlas can tell you what has been studied about Melanotan II. It cannot tell you how it would interact with your body, your history, or anything else you are taking, and nothing on this page is a reason to start.
A cyclic alpha-MSH analog originally designed for tanning research; it activates melanocyte-stimulating hormone receptors, producing both melanin and sexual arousal. The parent of PT-141. Not approved anywhere, with multiple FDA safety warnings and a large gray market.
The "Barbie drug." Tanning and libido. Multiple FDA warnings. Huge gray market.
What people take it for
These are the reasons people give for taking it. They are not effects it has been shown to have.
How it is supposed to work
Melanotan II is a broad, non-selective mimic of the natural hormone alpha-MSH, switching on several melanocortin receptors at once. Through MC1R in the skin it drives melanocytes to make more melanin, producing a tan without ultraviolet light. Through MC4R in the brain it suppresses appetite and triggers sexual arousal. Because it hits every melanocortin receptor rather than just one, it produces the full spectrum of effects, tanning, libido and appetite changes together, and a correspondingly wide range of side effects. The tan is real and appears within about five doses; so does everything else the drug touches.
- Step 1MC1R in skinIt drives melanocytes to make more melanin, producing a tan without ultraviolet light.
- Step 2MC4R in brainIt suppresses appetite and triggers sexual arousal.
- Step 3Every receptor at onceIt switches on several melanocortin receptors together, so the full range of effects arrives together.
Cyclic peptide of seven amino acids, alpha-MSH analog.
- Type
- Melanocortin agonist
- Size
- 7 amino acids
- Route
- Subcutaneous, every other day
- Tan onset
- ~5 doses
- Approved
- Nowhere
- US status
- Category 2 (restricted)
A Real Tan, Serious Risks
Melanotan II has a real, well-understood effect, and it is also, by most expert accounts, the least regulated, least studied and least safe peptide in the consumer space, so the honesty here is a warning. It has never been approved anywhere, is illegal to sell for human use in most countries, and is enforced unusually hard: Australia reclassified it in 2026 to the same schedule as MDMA, and in the US it sits on the restricted compounding list with criminal prosecutions of sellers already on record. The documented harms are serious, not theoretical: prolonged painful erections (priapism) that have required surgery, a case of muscle breakdown and kidney failure at a high dose, and cardiovascular effects. And there is the mole-and-melanoma question. Case reports link it to melanoma and it is mechanistically plausible, though reviews have not proven causation and suspect heavy sun-seeking explains much of the signal; worse, the widespread mole darkening it causes can mask the very cancers a user should be watching for. The human evidence base, meanwhile, is a few dozen people.
How it is taken
Injection
solution Melanotan II in a subcutaneous research preparation, compared with saline vehicle. The clinical abstracts do not establish finished-vial, reconstitution, or storage stability for gray-market products. Small phase I and erectile-dysfunction crossover studies.
Safety in detail
- It darkens existing moles and brings new ones, which makes a genuine skin cancer harder to spot, and case reports describe melanoma in users.
- Case reports also describe prolonged painful erections that required surgery, and muscle breakdown with kidney injury at a high dose.
Children and teenagers
Melanotan II is a cosmetic tanning and sexual-arousal peptide with no medical indication and no place in anyone under 18. The appearance pressures of tanning culture can reach adolescents, which makes this worth naming, but the combination of serious documented harms, an unregulated and often contaminated supply, and outright illegality means any use in a minor would be dangerous misuse. There is no version of pediatric use that is defensible.
What people get wrong
Often saidA UV-free tan makes Melanotan II a safe sunscreen substitute
ActuallyMelanotan II can increase pigmentation, but no study shows that gray-market use prevents skin cancer or replaces sun protection. It is unapproved and can darken or change moles.
Often saidIts side effects are only cosmetic
ActuallyEven the small clinical studies reported nausea, fatigue, yawning, and prolonged spontaneous erections, and later case reports describe more serious harms. Their frequency is unknown.
Who profits, and who pushes back
Dermatology & cancer bodies
Tanning injections are unlicensed and unsafe. Darkening moles can mask early melanoma, and case reports link use to atypical moles and renal infarction.
FDA, NHS, and other regulators
Melanotan II is not approved and is illegal to sell for human use. Purity, dose, and long-term safety are all unverified.
There is no legitimate Melanotan II product; the molecule’s only approved relatives, afamelanotide and PT-141, are separate regulated businesses. The Melanotan II economy is entirely unregulated: internet vendors, gyms, and tanning and beauty salons selling vials as "melanotan" or "research chemicals." It is one of the more heavily prosecuted peptides, with at least one US seller criminally convicted for nearly a million dollars in illegal sales and permanently barred. The profit here flows to operators with no accountability for a product regulators have uniformly warned against.
How we got here
Melanotan II is a synthetic cyclic heptapeptide analog of alpha-melanocyte-stimulating hormone (alpha-MSH) developed in the 1980s and 1990s by Hruby, Hadley, Dorr and colleagues at the University of Arizona as part of melanocortin receptor research. It is distinct from Melanotan I (afamelanotide, marketed as Scenesse), which is a linear MC1R-selective peptide with regulated medical use, whereas Melanotan II is an unapproved, non-selective melanocortin agonist sold on the gray market as a self-injected tanning agent nicknamed the "Barbie drug." The FDA-approved sexual-dysfunction drug bremelanotide (PT-141) is a simplified derivative of Melanotan II, carrying a free C-terminal carboxyl rather than the amide, which reduces MC1R activity relative to its parent.
Melanotan II was created in the 1980s at the University of Arizona by Victor Hruby and Mac Hadley, who reasoned that a peptide inducing a protective tan without UV might reduce skin cancer in sun-sensitive people. Development as a drug was halted over safety concerns, and it was never approved. Instead it splintered in two directions: it gave rise to PT-141, refined for sexual function, and stands beside afamelanotide, the selective tanning peptide approved for a rare light-sensitivity disorder. Melanotan II itself escaped into gym, salon and internet culture as a cosmetic tanning agent, and over time regulators moved against it, culminating in the US restricting its compounding in 2023 and Australia criminalizing it in 2026.
Early human development
1996 to 2000
Very small trials confirmed biological effects and exposed tolerability concerns.
- 1996Tanning activity and acute effects are documentedPigmentation increased in two participants. Nausea, fatigue, yawning, and spontaneous erections also occurred.
- 2000Erectogenic effects are tested in organic erectile dysfunctionSubcutaneous Melanotan II produced erectile responses in a small controlled study. It did not establish long-term safety or a tanning indication.
Post-development safety signals
2012 to 2020
Case reports describe serious harms but cannot measure their frequency.
- 2012Severe systemic toxicity is reported after injectionOne man developed muscle breakdown and kidney dysfunction after a 6 mg subcutaneous injection. Product identity and incidence cannot be established from one case.
The numbers behind the grade
- Type
- Tanning peptide
- Mechanism
- Non-selective melanocortin
- Approved
- Nowhere
- US
- Category 2 (restricted)
- Australia
- Schedule 9 (2026)
- Trial participants
- ~33
The people taking it
Users want a tan: fair-skinned people who tan poorly, tanning enthusiasts, and bodybuilders preparing a stage look. Use spans both sexes and spreads through salon and gym networks.
Famous as the "Barbie drug" or "tan jab," Melanotan II is one of the most recognized and most heavily enforced peptides in the world, widely used for cosmetic tanning despite being illegal for human use across most of it.
Melanotan II’s users are appearance-driven rather than medical: fair-skinned people who tan poorly, tanning-culture enthusiasts, competition bodybuilders preparing a stage look, and gym-goers who also value its libido and appetite effects. Use spans both sexes, with strong roots in tanning-heavy cultures. As with all gray-market compounds there is no reliable demographic data, only the visible communities and the salon-and-gym networks through which it spreads.
Used gray-market for cosmetic tanning, with appetite-suppressing and libido effects alongside, and sold through online vendors, gyms and salons. Not approved anywhere and increasingly criminalized. Its selective relatives, by contrast, are approved for medical use.
Set against the alternatives
Melanotan II is the non-selective original from which two more targeted molecules were drawn, and that family tree is the clearest way to judge it. PT-141 (bremelanotide) is the refined, libido-focused derivative that shed most of the tanning and went on to FDA approval for sexual desire. Afamelanotide, essentially the selective tanning relative, is FDA-approved as an implant for a rare light-sensitivity disorder and is the legitimate way to obtain a melanocortin tanning effect under medical supervision. Melanotan II sits between these two approved relatives as the unapproved, non-selective, and by far the riskiest of the three, offering the tan that afamelanotide does and the libido effect that PT-141 does, but without the safety, dosing control or oversight of either.
What we do not know
- Whether Melanotan II independently raises melanoma risk, or whether the signal is driven by users’ sun-seeking behavior.
- What chronic, non-selective melanocortin stimulation does to the body over years.
- How much harm the mole-darkening effect causes by masking real skin cancers.
- The true scale of injuries from unregulated, often contaminated product.
- Why an unapproved, criminalized peptide remains so widely used for cosmetic reasons.
What could change
Tightening enforcementRegulators are moving toward stricter control, not looser, as the 2026 Australian reclassification shows.The approved alternativeAfamelanotide remains the only lawful melanocortin tanning option, under medical supervision.Melanoma researchOngoing work may finally settle whether Melanotan II independently affects melanoma risk.Harm awarenessGreater documentation of priapism, kidney and cardiovascular cases may shape public understanding.
Legal status
Melanotan II has never been approved by any regulator and is illegal to sell for human use in most countries. In the US it is on the restricted compounding list and cannot be legally compounded, a status expected to persist; in Australia it is now treated as a serious controlled substance. It is sold only through unregulated online vendors, gyms and salons. The sole lawful way to get a melanocortin tanning effect is afamelanotide, a prescription implant for a rare medical condition, not a cosmetic product.
Status current as of July 2026. Regulatory positions change, sometimes quickly.
The market for this
What follows describes how this is bought and sold. It is not a buying guide and it is not an endorsement of any seller.
There is no lawful way to buy Melanotan II for cosmetic use; it is sold only through unregulated vendors, gyms and salons, which is illegal for human use in most places and carries serious safety and, in some countries, legal risk. The responsible answer is not to, and anyone determined to use it should at minimum have a dermatologist involved and baseline mole mapping done. The approved relative afamelanotide is available only by prescription for its specific medical indication.
Gray-market vials are inexpensive, which is part of the appeal, but the price excludes the real costs: an unverified and possibly contaminated product, no medical oversight, and the dermatologic monitoring that responsible use would require. There is no legitimate cosmetic product to price against.
Essentially all Melanotan II comes from unregulated manufacture, much of it overseas, sold without meaningful quality control through online and in-person gray-market channels. Contamination, mislabeling and uncertain dose are routine concerns, and third-party verification is rare, which compounds the drug’s already serious intrinsic risks.
China and unregulated manufactureMost Melanotan II is synthesized in unregulated overseas facilities and sold online or through gyms and salons, with real contamination and content risk.Gyms and beauty salonsA distinctive retail channel, where "tan jabs" are sold informally alongside fitness and beauty services.Heavily enforcedIt cannot be legally compounded in the US (Category 2), and Australia treats possession as a serious criminal matter, making its supply genuinely illicit in many places.The legitimate alternativeThe only lawful melanocortin tanning option, afamelanotide, comes through a regulated implant for a specific medical condition, not this gray market.
At a glance
- Effect
- Tanning + arousal
- Parent of
- PT-141
- FDA
- Multiple warnings
- Origin
- University of Arizona
What this entry does not yet cover
What follows is unfinished work on our side, not a finding about Melanotan II.
Nothing outstanding on this one.
Sources
MHRA warns against unlicensed melanotan tanning injections and nasal sprays; products are unlicensed and their safety, quality and efficacy are unproven
MHRA received 18 reports covering 74 suspected reactions (stomach, heart, blood and eye disorders) and shut down UK supply websites
MHRA FOI response detailing side-effect reports for melanotan II products in the UK
TGA states melanotan-II is not approved in Australia, its development as a medicine was halted for safety reasons, it is illegal to supply without prescription, and risks include skin cancer, increased moles/freckles, kidney dysfunction and brain swelling
TGA enforcement: individual issued 27 infringement notices for allegedly supplying Melanotan II
FDA issued a 2007 warning letter to Melanocorp Inc.; melanotan II is an unapproved new drug and illegal to market as an injectable tanning product
FDA debarment order against Edward Manookian following felony convictions relating to marketing of a drug product (melanotan II tanning products)
Peer-reviewed case report: 39-year-old man developed systemic sympathomimetic toxicity, rhabdomyolysis (CPK peaking ~17,773 IU/L) and renal dysfunction after a 6 mg subcutaneous melanotan II injection
Nelson ME, Bryant SM, Aks SE. Clin Toxicol (Phila). 2012;50(10):1169-1173
Peer-reviewed case report and literature review associating melanotan II with renal infarction and reviewing other adverse events
Case report: melanoma in-situ associated with melanotan II use, consistent with new/changing pigmented lesions in users
Cancer Research UK: melanotan injections are sold illegally and are possibly unsafe; can cause moles to change and grow
Clinical overview of melanotan II: melanocortin agonist mechanism, unlicensed status, and adverse effects including nausea, darkening/changing moles, priapism and systemic toxicity
The studies that matter
Dorr et al, pilot Phase 11996
An early small clinical study confirmed Melanotan II as a superpotent tanning peptide; the human evidence base remains tiny, on the order of a few dozen people across published trials.
Hadley and Dorr, melanocortin reviews2000s
Documented the milestones and pharmacology of melanocortin peptides, including the tanning and systemic effects.
Melanoma reviews2013 and 2021
Concluded there is no conclusive evidence that Melanotan II causes melanoma, and that the higher melanoma rate seen in users is probably explained by their greater UV exposure and sun-seeking behavior.
In vivo melanoma study2020
Found, paradoxically, that Melanotan II suppressed melanoma progression in an animal model, underscoring how unsettled the cancer question is.
Harm case reportsvarious
Published reports of priapism, rhabdomyolysis with kidney injury and cardiovascular events, mostly at higher-than-typical doses.