What melanotan 2 is
Melanotan 2, written Melanotan-II or MT-II in the papers, is a synthetic, cyclic (ring-shaped) peptide of seven amino acids. The 1996 paper on a pilot study of it in people describes it as a cyclic heptapeptide analog of alpha-melanocyte stimulating hormone, and as a lactam-bridged molecule. A later paper by several of the same authors calls it a non-selective melanocortin receptor agonist.
Where it stands with the FDA
Melanotan 2 isn't an FDA-approved drug. A 2016 FDA notice in the Federal Register calls it an unapproved new drug. The notice records that on or about August 30, 2007, a company that advertised it online as an injectable tanning product received a warning letter from FDA.
It was nominated for use in compounded drugs and placed in category 2 of FDA's interim policies, the group for substances that may present significant safety risks. FDA's page on those substances, current as of April 22, 2026, lists it among the ones withdrawn by the nominators.
That page still gives the potential risks FDA identified. It says compounded drugs containing melanotan 2 may pose a risk for immunogenicity (the drug setting off an immune reaction) for certain routes of administration, because of the potential for aggregation or peptide-related impurities. It also says published case reports discuss serious adverse events including melanoma, posterior reversible encephalopathy syndrome, sympathomimetic toxidrome and priapism.
As updated May 14, 2026, FDA's list of substances nominated under section 503A doesn't have melanotan 2 in any of its categories.
A separate FDA page, current as of April 15, 2026, says the agency will host an advisory committee meeting before the end of February 2027, and names Melanotan II among the substances the committee will discuss as being considered for the 503A bulks list. It says the meeting's time and location will be scheduled in the coming months. The documents don't say how that agenda and the withdrawal fit together, so this page doesn't guess.
What the trials tested
The doses below are what published trials tested. They aren't a recommendation, no approved use stands behind them, and they were set per kilogram of body weight, so the amount differed from person to person.
A pilot phase I study published in 1996 gave melanotan 2 by injection under the skin to 3 normal male volunteers. The first dose the trial tested was 0.01 mg/kg. Two subjects were escalated by 0.005 mg/kg increments to 0.03 mg/kg and one to 0.025 mg/kg. The abstract says the 0.03 mg/kg dose produced Grade II somnolence and fatigue in one of two subjects, and that mild nausea, not requiring antiemetic treatment, was reported at most dose levels. It reports spontaneous erections that came and went for 1 to 5 hours after dosing, depending on the dose, and increased pigmentation in the face, upper body and buttock in two subjects.
A 1998 double-blind, placebo controlled crossover study tested it in 10 men with erectile dysfunction of no known organic cause. The abstract says clinically apparent erections developed in 8 of the 10, and that nausea, stretching and yawning, and decreased appetite were reported more often after melanotan 2 than after placebo, with none requiring treatment. The dose it names is 0.025 mg/kg.
In 2000 several of the same authors reviewed their experience with 20 men. That abstract says nausea and yawning were frequently reported side effects, and that at a dose of 0.025 mg/kg, 12.9% of subjects had severe nausea. It doesn't say how many subjects that figure covers.
Storing melanotan 2
None of the documents this page rests on says how to store melanotan 2, as a dry powder or as a mixed vial, so this page doesn't either.
There's no approved label for melanotan 2, so nothing official says how long a mixed vial keeps.
Melanotan 2 dosage calculator questions
How do I turn a melanotan 2 dose into syringe units?
Divide the dose by the concentration to get millilitres, then multiply by 100. A 5 mg vial mixed with 2 mL is 2.5 mg/mL, so one unit on an insulin syringe holds 25 mcg and ten units hold 250 mcg.
How much bacteriostatic water goes in a 5 mg vial of melanotan 2?
There's no single right amount. The water only sets the concentration, and the amount of melanotan 2 in the vial stays the same. With 5 mg, 1 mL makes 5 mg/mL, 2 mL makes 2.5 mg/mL and 3 mL makes 1.667 mg/mL. Choose the amount that puts your dose somewhere between about 10 and 40 units, where it's easiest to read.
Is melanotan 2 approved by the FDA?
No. A 2016 FDA notice in the Federal Register calls melanotan 2 an unapproved new drug. It was nominated for use in compounded drugs, placed in the FDA category for substances that may present significant safety risks, and then withdrawn by its nominators. An FDA page current as of April 15, 2026 lists it for discussion at an advisory committee meeting to be held before the end of February 2027.
Does this page tell me how much melanotan 2 to take?
No. There's no FDA-approved melanotan 2 product, so there's no approved dose to point to. The published trials set their doses by body weight, and this page reports those only as what the trials tested. The dose box starts empty for that reason, and the chart only converts.
More peptide calculators by name
The same instrument, set up one peptide at a time. For any other vial, use the peptide reconstitution calculator.