Melanotan 1 vs 2: How Afamelanotide, Melanotan II and PT-141 Differ
The gap between Melanotan 1 and Melanotan 2 is really about receptor selectivity and what regulators have done with each. Melanotan 1 (afamelanotide) is a linear peptide aimed mostly at MC1R, and it went on to become Scenesse, an implant registered by the TGA for a rare disorder of light sensitivity. Melanotan II is a smaller, cyclic peptide that switches on several melanocortin receptors, has never gained approval in any country, and has drawn repeated TGA warnings over tanning products.
Shop Melanotan Australia With a Quick Comparison of Melanotan 1 vs 2
Every compound in this group is an analogue of alpha-melanocyte stimulating hormone (alpha-MSH), the 13-residue peptide that signals melanocytes through the MC1R receptor to produce eumelanin. Scientists at the University of Arizona created them during the 1980s and 1990s, after which each one followed a very different path.
| Melanotan 1 (afamelanotide) | Melanotan II | PT-141 (bremelanotide) | |
|---|---|---|---|
| Molecular form | [Nle4, D-Phe7]-alpha-MSH, a 13-residue linear chain | Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2, a cyclic lactam heptapeptide | Ring-shaped heptapeptide very similar to Melanotan II, with a different C-terminus |
| Receptor targets | Chiefly MC1R (pigmentation) | Broad, covering MC1R, MC3R, MC4R and MC5R | Investigated for central MC4R effects |
| Approved product | Scenesse, a 16 mg implant for erythropoietic protoporphyria (EU 2014, US 2019, TGA 2020) | None in any country | Vyleesi injection (US FDA, 2019) for low sexual desire in premenopausal women |
| Primary research application | Pigmentation and photoprotection models | Wide melanocortin receptor pharmacology | Central melanocortin signalling |
For anyone running experiments, receptor coverage is what separates them in practice. When the work centres on pigment output at MC1R, Melanotan 1 gives cleaner results. Melanotan II engages multiple receptor subtypes together, which accounts for its strength as well as its lengthy list of off-target effects. Researchers can buy Melanotan 1 online in Australia as a 10 mg vial for MC1R selective work.
Buy Melanotan 1 Online and Learn How It Became a TGA Registered Implant
Clinuvel Pharmaceuticals, based in Melbourne, developed afamelanotide as a controlled-release implant instead of an injection. The key evidence came from two randomised, placebo-controlled trials that Langendonk and colleagues published in the New England Journal of Medicine in 2015, enrolling 74 patients in Europe and 94 in the United States. Both focused on erythropoietic protoporphyria (EPP), an inherited condition in which sunlight triggers severe pain. In the American trial, median pain-free time spent in direct sunlight across six months reached 69.4 hours on afamelanotide compared with 40.8 hours on placebo. Most adverse events were mild, and serious events were judged unrelated to the drug.
In October 2020 the TGA approved Scenesse to prevent phototoxicity in adults with EPP, making it the first EPP therapy registered in Australia. A trained health professional inserts the implant. This registration applies only to Clinuvel's EPP implant. Research-grade Melanotan 1 does not become a registered medicine because of it, and it is in no way an approval for tanning.
Order Melanotan II for Research Knowing What the Early Human Pilot Showed
Researchers designed Melanotan II to outperform Melanotan 1 in potency and stability by closing it into a seven-residue ring. Its sole published pilot phase I study, by Dorr and colleagues (Life Sciences, 1996), administered small subcutaneous doses to healthy men across two weeks. After just five doses, tanning was visible on the face, upper body and buttocks. The same study also recorded the effects that ended its future as a tanning drug. These were mild nausea at most dose levels, a stretching and yawning complex and spontaneous erections of one to five hours. One volunteer at the highest dose also had grade II somnolence and fatigue.
PT-141 exists because of those erections. The sexual effects seen with Melanotan II steered scientists toward central MC4R signalling, and bremelanotide was derived from it for that reason. No country ever approved Melanotan II itself for any purpose. Melanotan II is for sale in Australia as a 10 mg vial for receptor pharmacology research only.
Buy Research Peptides With the Case Reports on Melanotan II Side Effects in Mind
Much of the knowledge on melanotan ii side effects comes not from trials but from dermatology case reports involving people who used unlicensed tanning products. In the BMJ in 2009, Langan and colleagues described changing moles associated with the "sun tan jab", with biopsied lesions ranging from benign to severely dysplastic naevi. In 2011 Paurobally and colleagues reported melanotan-associated melanoma in the British Journal of Dermatology. Other papers document eruptive and atypical naevi emerging within weeks of first use, and separate case reports describe priapism, rhabdomyolysis and acute kidney injury.
Two caveats matter here. Case reports do not establish causation, and a 2023 UNSW explainer on the TGA warning points out that a melanoma link has not been definitively proven. In addition, the products involved had unknown contents, so nobody could know the dose or purity. Neither caveat makes the signal comforting, since fast-changing moles are precisely what dermatologists watch for in early melanoma, and Melanotan II makes those changes harder to interpret.
Shop Melanotan II Australia Legally and Know Where the TGA Stands on Injections, Sprays and Before and After Photos
Australians have been warned many times by the TGA against melanotan tanning products. As set out on tga.gov.au, the regulator's view is that melanotan is a prescription-only medicine and is not approved for tanning. Supplying tanning products that contain it without a prescription is illegal in every form, whether injection, nasal spray, tablet or cream. None of these products has been assessed for quality, safety or efficacy.
The TGA has also put products on the market to the test. According to one safety alert, its laboratory analysed five nasal spray bottles, each labelled "30 mg", and found anywhere from 22 mg to 54 mg of Melanotan II per bottle, and the person supplying them received 27 infringement notices. This is the core issue with melanotan ii injections and melanotan ii nasal spray products marketed for tanning, because the label gives no reliable indication of the contents.
Social media posts showing melanotan ii before and after photos are the promotional side of that trade. They reveal colour, but not safety, not dose, and not what happened to the person's moles. Our stance is direct. A before and after picture signals a questionable sales channel, and none of our melanocortin peptides are intended for tanning or any human use.
Order PT-141 and See Where Bremelanotide Fits in the Family
In June 2019 the US FDA approved bremelanotide as Vyleesi, an autoinjector for acquired, generalised hypoactive sexual desire disorder in premenopausal women. Its label reveals the family likeness, with nausea reported in 40 percent of trial patients and focal hyperpigmentation of the face, gums or breasts in roughly 1 percent, which may persist after treatment stops. Even a molecule tuned away from pigmentation still interacts with MC1R.
For studies on central melanocortin signalling, the PT-141 research peptide is the focused choice, and the PT-141 reconstitution calculator takes care of solution maths in the lab. Researchers examining hypothalamic reproductive signalling via another route frequently compare it with kisspeptin, which works through the KISS1 receptor instead of a melanocortin receptor. Order PT-141 online from Australian stock as a 10 mg vial, each lot with its own certificate.
Buy the Right Melanocortin Peptide for Your Research Model
Melanotan 1 is the stronger choice for pigmentation and photoprotection models, offering a single main receptor, human evidence and an approved relative. Melanotan II makes sense only when broad melanocortin activation is the aim of the study. PT-141 lies between the two for work focused on MC4R. You will find all three in our melanocortin peptide collection, and every lot has a certificate on the COA lookup.
Shop Melanotan 1, Melanotan II and PT-141 for Sale Online in Australia
NovaPep holds all three in Australian stock and sells each online. Order Melanotan 1 as a 10 mg vial for pigmentation models centred on MC1R. Choose Melanotan II, available as a 10 mg vial or a 10 mL nasal spray, when your experiment needs broad melanocortin receptor activation. Pick PT-141 (bremelanotide), offered as a 10 mg vial or a 10 mL spray, for MC4R studies. Each lot carries an independent identity and purity certificate under the number printed on the vial. Go for the vial format if you want to set your own concentration, and include bacteriostatic water in your order.
NovaPep provides these compounds to adults 18+ strictly for laboratory research. They are not for human or veterinary use, not for tanning, and nothing on this page constitutes dosing advice. Store lyophilised vials cold and away from light, and see our peptide storage guide for why melanocortin peptides containing tryptophan residues are vulnerable to light and oxidation.
Melanotan 1 vs 2: How Afamelanotide, Melanotan II and PT-141 Differ FAQ
Which is stronger, Melanotan 1 or Melanotan 2?
Milligram for milligram, Melanotan II is the more potent compound. Its cyclic shape adds stability, and it activates several melanocortin receptors (MC1R, MC3R, MC4R and MC5R), whereas Melanotan 1 works mostly at MC1R. That wider activity also explains why Melanotan II produces nausea, yawning and erections, which are seldom linked to afamelanotide.
Are Melanotan 1 and Scenesse the same thing?
Scenesse is a 16 mg controlled-release implant containing afamelanotide, the same molecule as Melanotan 1. The TGA has registered it solely to prevent phototoxicity in adults with erythropoietic protoporphyria, and a trained health professional inserts it. Research-grade Melanotan 1 is not Scenesse and has no status as a registered medicine.
Can Melanotan II be legally used for tanning in Australia?
No. According to the TGA, melanotan is a prescription-only medicine with no approval as a tanning agent, and supplying tanning products containing it without a prescription is illegal in every form, injections and nasal sprays included. The TGA has issued infringement notices to those supplying such products.
What side effects are linked to Melanotan II?
In the 1996 human pilot, researchers noted nausea, yawning and stretching, spontaneous erections and fatigue. Case reports from users of unlicensed tanning products describe new or quickly changing moles, dysplastic naevi and melanoma, along with isolated cases of priapism and kidney injury. Case reports do not prove causation, yet the pattern worries dermatologists.
Does a Melanotan II nasal spray differ from injections?
Not in the eyes of the TGA, which considers it illegal to supply melanotan tanning products without a prescription in any form. When its laboratory tested nasal sprays labelled 30 mg, it measured between 22 and 54 mg per bottle, showing that unregulated sprays can contain doses far removed from the label.
Where can I order Melanotan 1 or Melanotan 2 online in Australia?
NovaPep sells both online from Australian stock for laboratory research. Melanotan 1 comes as a 10 mg vial and Melanotan II as a 10 mg vial or a 10 mL nasal spray, each backed by an independent certificate matched to the lot number. Neither product is sold for tanning, and we offer no dosing or personal-use advice. Melanotan II has no TGA approval.