Melanotan II is unapproved, has never completed a dose-finding programme, and has no label anywhere. Nothing below is a protocol. The figures are described to explain what the published record does and does not contain.
Overview
There is no validated Melanotan II dosing schedule, and that is a substantive finding rather than a caveat. Approved drugs get their numbers from phase 1 dose-escalation and phase 2 dose-ranging studies that map effect against toxicity. Melanotan II never went through either. Development moved to a refined successor instead, so the milligram figures circulating in tanning communities were not inherited from a research programme — they were invented by users and passed along.
The only dose in the clinical literature
The single controlled human study used 0.025 mg/kg subcutaneously in ten men with psychogenic erectile dysfunction, measuring erections by RigiScan over six hours. Eight of ten developed clinically evident erections; mean tip rigidity above 80% lasted 38.0 minutes versus 3.0 on placebo (p=0.0045). Transient nausea, yawning and stretching, and decreased appetite were more frequent on the peptide (Wessells et al., J Urol 1998).
Two things follow. That dose is weight-based, so for an 80 kg adult it works out to roughly 2 mg — and it was chosen to produce an erectile response over a single session, not to produce pigmentation over weeks. Nobody has published what amount produces tanning, how long it takes, or what happens with repeated exposure. Borrowing the erectile-trial figure for a cosmetic purpose is using a number to answer a question it was not asked.
What a dosing error looks like
The literature contains one detailed account of what happens when the hand-mixed format goes wrong. A 39-year-old man injected 6 mg of Melanotan II purchased over the internet — six times the starting dose he reported having been advised to use — and arrived in an emergency department two hours later with body aches, sweating, anxiety, mydriasis, tremor, and a heart rate that peaked at 146 bpm. His creatine phosphokinase climbed from 1,760 to 17,773 IU/L within 12 hours, with creatinine at 2.25 mg/dL. He required three days of intensive care with fluids and bicarbonate for rhabdomyolysis. Mass spectrometry confirmed the injected substance was genuinely Melanotan II (Nelson et al., Clin Toxicol 2012).
This case is instructive precisely because nothing was counterfeit. The peptide was real; the quantity was wrong. That is the failure mode built into a lyophilized vial of unverified content, reconstituted by hand, drawn into a syringe whose unit markings measure volume rather than dose.
Why there is no titration logic to follow
With approved drugs, "start low and go slow" works because a label defines what low, high and slow mean, and because the effect being titrated toward is measurable. Neither condition holds here.
- No ceiling is defined. Nothing establishes an upper limit, so there is no known distance between a common amount and a harmful one.
- The side effects are not dose-limiting warnings — they are the pharmacology. Nausea, flushing and appetite suppression appeared in the controlled trial at a therapeutic dose, so their presence does not mark a boundary being crossed.
- The serious events are not gradual. Ischemic priapism requiring surgical decompression (Mallory et al., Sex Med 2021) and renal infarction (Peters et al., CEN Case Rep 2020) are acute events, not endpoints a person titrates toward and stops before.
- The pigmentary risk is cumulative and silent. Mole darkening and new atypical naevi do not announce themselves during a dose escalation.
A 2017 review of unregulated α-MSH analogue use names uncertainty about preparation, administration and dosing as a defining feature of this market (Habbema et al., Int J Dermatol 2017).
What a real dosing framework looks like
Both of Melanotan II's close relatives illustrate the difference. Bremelanotide is a fixed-dose 1.75 mg single-use autoinjector, capped at one dose per 24 hours and 8 per month, with an 8-week reassessment point — limits derived from measured blood-pressure and hyperpigmentation data (Vyleesi label). Afamelanotide is a 16 mg implant placed by a clinician every two months. See PT-141 and Melanotan I.
In both cases the numbers exist because a programme generated them and a regulator reviewed them. For Melanotan II, the corresponding numbers were never produced, and no amount of community consensus substitutes for them.