Pinc PeptideThe girly peptide research blog

Melanotan II · Dose evidence · updated 8 October 2026

Melanotan II dosage: what studies actually used

The short answer

The only human studies of melanotan II that we found are three small studies of men, published from 1996 to 2000, all by injection under the skin at doses set by body weight1345. A tanning pilot in 3 men used 0.01 to 0.03 mg/kg3. Two erection trials in 10 men each reported results at 0.025 mg/kg, and a 2007 review by the same research group says the 1998 trial gave doses from 0.025 to 0.157 mg/kg145. FDA has approved no melanotan II product, so no dose is established for any use6. Afamelanotide (Scenesse) and bremelanotide (Vyleesi) are different molecules with their own approved doses, and those doses do not carry over78.

Not dosing advice. This page reports doses that studies and approved labels used, with their sources. It does not recommend a dose, and we do not give mixing, injection or unit-conversion instructions. Gray-market vials often do not contain what their label says. How we report doses.

Every dose studied in people

StudyWhoPeopleDose and routeWhat happened
Wessells 2000, double-blind placebo-controlled crossover trial Men with erectile dysfunction and physical (organic) risk factors 10 0.025 mg/kg, given twice, and placebo given twice
Injection under the skin · Each injection followed by 6 hours of monitoring		 Men reported erections after 12 of 19 injections of the drug and 1 of 21 placebo doses, and rigidity above 80% at the tip of the penis, measured by a RigiScan monitor, lasted 45.3 minutes on average versus 1.9 minutes on placebo (P = 0.047)5. Sexual desire was significantly higher after the drug than after placebo5. Nausea and stretching or yawning were more common on the drug, and 4 of the 19 drug injections were followed by severe nausea5.
Wessells 1998, double-blind placebo-controlled crossover trial Men with erectile dysfunction of no known physical cause (psychogenic) 10 0.025 to 0.157 mg/kg, according to a 2007 review by the same research group
Injection under the skin · Each dose followed by 6 hours of monitoring		 Erections developed in 8 of 10 men, and rigidity above 80% at the tip lasted 38.0 minutes on average versus 3.0 minutes on placebo (p = 0.0045)4. Nausea, stretching and yawning, and reduced appetite were more common after the drug, but none needed treatment, and the authors called the side effects manageable at 0.025 mg/kg4. A 2007 review by the same group, the source of the dose range, says these side effects rose with the dose and were mild at 0.025 mg/kg, the dose the researchers preferred1.
Dorr 1996, pilot Phase 1 study, single-blind, with saline on alternate days Healthy men 3 0.01 mg/kg at first, raised in 0.005 mg/kg steps to 0.025 mg/kg (1 man) or 0.03 mg/kg (2 men); 5 doses of the drug in all
Injection under the skin · 2 weeks of weekday injections, alternating the drug with saline		 Two of the 3 men had darker skin on the face, upper body and buttock 1 week after the last dose, measured with a light-reflectance meter and by eye3. Mild nausea came at most dose levels, 0.03 mg/kg caused grade II sleepiness and fatigue (on the WHO scale) in 1 of the 2 men who got it, and spontaneous erections came and went for 1 to 5 hours after doses3.

Studies, animals and users: kept apart

Doses below are what studies used or what a label says. They are not advice, and gray-market products may not contain what their label says.

In human studies

The trials used body-weight doses injected under the skin. The 1996 pilot started 3 men at 0.01 mg/kg and raised the dose in 0.005 mg/kg steps to 0.025–0.03 mg/kg, alternating with saline on weekdays for 2 weeks. After 0.03 mg/kg caused somnolence and fatigue in 1 of 2 men, the authors recommended 0.025 mg/kg per day for future studies3. In the erectile dysfunction trials, the 1998 trial gave doses from 0.025 to 0.157 mg/kg, according to a 2007 review by the same research group, and its abstract reports results at 0.025 mg/kg14; the 2000 trial gave 0.025 mg/kg twice and placebo twice5. We found no human study of the nasal spray, of courses longer than 2 weeks or of the fixed microgram doses used online1011.

In animal studies

In rats, 2 mg/kg injected into the abdominal cavity (intraperitoneal) once daily for 4 days reduced food intake and weight gain12. In hormone-primed female rats, 1 and 3 mg/kg intravenously increased solicitation behaviors13. In lean and diet-induced obese rats, a brain infusion of 1 nmol/day for 6 days reduced body weight and visceral fat14. A rat study of how the body handles the drug (pharmacokinetics) used 0.3 mg/kg intravenously15. These are animal doses, not human doses.

What users report Anecdotal · not validated · not a recommendation

One dosing site lists 250 µg (micrograms) to 1 mg a day, injected under the skin9.

Half-life and how it is taken

Routes
  • Subcutaneous injection (the only route with human trial data we found)
  • Nasal spray (sold widely; no human trial data found)
  • Tablets (named by Australian news as a form it can be sold in; no human data found)
  • Intravenous, intraperitoneal and brain infusion (animal studies only)

Side effects at the studied dose and beyond

Nausea and yawning were frequent side effects in the trials: pooling both erection trials, the research group reported that ‘12.9% of subjects had severe nausea’ at 0.025 mg/kg, without giving the count17.

Outside studies, case reports describe harm after doses people chose themselves. A 39-year-old man who injected 6 mg of melanotan II bought online developed a racing heart, sweating and muscle breakdown, with creatine kinase (CPK, a marker of muscle damage) peaking at 17,773 IU/L, and he spent 3 days in intensive care18. A 55-year-old man arrived at an emergency department with a painful erection that had lasted 30 hours after he injected 2 mg; he needed surgery, and 15 weeks later he reported new erectile dysfunction19. These are single cases: they show what can happen, not how often1819.

What melanotan II products were found to contain

A laboratory that bought vials from three online shops, each of which said its vials held 10 mg, found 4.32 to 8.84 mg of melanotan II, and unknown impurities of 4.1 to 5.9% in vials from two of the shops20. 7NEWS reported on 18 August 2026 that Australia’s Therapeutic Goods Administration (TGA) had recently tested five bottles of a nasal spray labeled ‘Pure Tans Triple Strength 30 MG’ and estimated that they held 22 mg to 54 mg of melanotan II21. As of 1 October 2026, the testing service Finnrick listed 182 tests of melanotan II products from 45 vendors, dated 19 February 2025 to 14 September 2026: 110 passed, 67 failed and 5 were incomplete, under a standard of at least 99.5% purity and a dose within 35% of the label22.

Questions people ask

How much melanotan II should I take?

No dose of melanotan II is established. Its three small studies in men injected doses set by body weight: 0.01 to 0.03 mg/kg in a tanning pilot, and 0.025 mg/kg in two erection trials, one of which also gave doses up to 0.157 mg/kg, according to a 2007 review1345. Melanotan II is not an approved drug, and US pharmacies may not compound it6232425.

What dose of melanotan 2 was used for tanning?

The only tanning study we found gave 3 healthy men 5 doses over 2 weeks, starting at 0.01 mg/kg and rising to 0.025 or 0.03 mg/kg3. Two of the 3 had darker skin a week after the last dose3.

Is the melanotan II dose the same as PT-141?

No. The 1.75 mg Vyleesi dose is for bremelanotide, a different molecule, and only for premenopausal women with acquired, generalized hypoactive sexual desire disorder7. Melanotan II’s studies gave men doses by body weight35.

What is the dose of melanotan nasal spray?

There is no studied nasal dose: every human study we found gave melanotan II by injection under the skin135. 7NEWS reported in August 2026 that when Australia’s TGA tested five bottles of one spray labeled 30 mg, it estimated that they held 22 mg to 54 mg of melanotan II21.

What happens if you take too much melanotan 2?

In the 1998 erection trial, side effects such as nausea, yawning and reduced appetite rose with the dose, according to a 2007 review by the same research group1. Case reports describe a man who injected 6 mg and spent 3 days in intensive care with muscle breakdown, and another whose erection lasted 30 hours after 2 mg and needed surgery1819.

Go deeper

Sources

  1. 1Melanocortin receptors, melanotropic peptides and penile erection Current Topics in Medicinal Chemistry, 2007. pmc.ncbi.nlm.nih.gov
  2. 2Afamelanotide, CID 16197727 PubChem, U.S. National Library of Medicine, accessed 7 Oct 2026. pubchem.ncbi.nlm.nih.gov
  3. 3Evaluation of melanotan-II, a superpotent cyclic melanotropic peptide in a pilot phase-I clinical study Life Sciences, 1996. pubmed.ncbi.nlm.nih.gov
  4. 4Synthetic melanotropic peptide initiates erections in men with psychogenic erectile dysfunction: double-blind, placebo controlled crossover study The Journal of Urology, Aug 1998. pubmed.ncbi.nlm.nih.gov
  5. 5Effect of an alpha-melanocyte stimulating hormone analog on penile erection and sexual desire in men with organic erectile dysfunction Urology, 1 Oct 2000. pubmed.ncbi.nlm.nih.gov
  6. 6Drugs@FDA data (openFDA drugsfda endpoint): search for melanotan as an active ingredient, no matches U.S. Food and Drug Administration (openFDA), 29 Sep 2026. api.fda.gov · data query
  7. 7VYLEESI (bremelanotide injection) prescribing information Cosette Pharmaceuticals via DailyMed (U.S. National Library of Medicine), 13 Nov 2025. dailymed.nlm.nih.gov
  8. 8SCENESSE (afamelanotide) implant prescribing information Clinuvel via DailyMed (U.S. National Library of Medicine), 11 May 2026. dailymed.nlm.nih.gov
  9. 9Melanotan II (10 mg Vial) Dosage Protocol PeptideDosages.com, 20 Sep 2026. peptidedosages.com
  10. 10PubMed search: melanotan in titles or abstracts, limited to clinical trials (8 results; 4 report the three melanotan II studies, 4 test melanotan I) National Library of Medicine (PubMed), accessed 8 Oct 2026. pubmed.ncbi.nlm.nih.gov
  11. 11ClinicalTrials.gov search for ‘melanotan’ (1 study: the ‘example’ record NCT07437560) ClinicalTrials.gov, accessed 8 Oct 2026. clinicaltrials.gov
  12. 12MTII administered peripherally reduces fat without invoking apoptosis in rats Physiology & Behavior, Jul 2003. pubmed.ncbi.nlm.nih.gov
  13. 13The melanocortin agonist, melanotan II, enhances proceptive sexual behaviors in the female rat Pharmacology, Biochemistry and Behavior, Nov 2006. pubmed.ncbi.nlm.nih.gov
  14. 14Unabated anorexic and enhanced thermogenic responses to melanotan II in diet-induced obese rats despite reduced melanocortin 3 and 4 receptor expression Journal of Endocrinology, Jul 2004. pubmed.ncbi.nlm.nih.gov
  15. 15A comparison of HPLC and bioassay methods for plasma melanotan-II (MT-II) determination: application to a pharmacokinetic study in rats Biopharmaceutics & Drug Disposition, Jul 1994. pubmed.ncbi.nlm.nih.gov
  16. 16Bremelanotide (CID 9941379) PubChem, NCBI, accessed 1 Oct 2026. pubchem.ncbi.nlm.nih.gov
  17. 17Melanocortin receptor agonists, penile erection, and sexual motivation: human studies with Melanotan II International Journal of Impotence Research, Oct 2000. pubmed.ncbi.nlm.nih.gov
  18. 18Melanotan II injection resulting in systemic toxicity and rhabdomyolysis Clinical Toxicology, Dec 2012. pubmed.ncbi.nlm.nih.gov
  19. 19Melanotan Tanning Injection: A Rare Cause of Priapism Sexual Medicine, Feb 2021. pubmed.ncbi.nlm.nih.gov
  20. 20Identification and characterization by LC-UV-MS/MS of melanotan II skin-tanning products sold illegally on the Internet Drug Testing and Analysis, Feb 2015. pubmed.ncbi.nlm.nih.gov
  21. 21MT2 ‘Barbie-tan’ peptide warning as TGA seizes nasal spray with wildly different doses 7NEWS (Australia), 18 Aug 2026. 7news.com.au
  22. 22Melanotan II Safety Testing Results & Vendor Ratings Finnrick, accessed 1 Oct 2026. finnrick.com
  23. 23Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks U.S. Food and Drug Administration, 22 Apr 2026. fda.gov
  24. 24Bulk Drug Substances Nominated for Use in Compounding Under Section 503A of the Federal Food, Drug, and Cosmetic Act (categories list) U.S. Food and Drug Administration, 14 May 2026. fda.gov
  25. 25FDA to Remove 12 Popular Peptides from the Category 2 ‘Do Not Compound’ List Frier Levitt, 16 Apr 2026. frierlevitt.com

Not medical advice. Talk to a licensed clinician before using any drug. Report an error.