Melanotan I vs Melanotan II
There is no winner on this page. What is set side by side is the published record behind each one, which is the part the two are rarely compared on.
Both in Melanocortin and hormonal
One letter apart, and neither number transfers to the other. Melanotan-1's molecule is the approved drug and the product is not: the trials used a 16 mg implant placed by a physician every 60 days, which releases most of its content in the first two days, and a weekly injection of a peptide with a half life measured in hours produces the opposite shape. Melanotan-II's convention runs below what was tested rather than above, between a seventh and a third of the doses given in four trials, and what those trials measured in 43 men was erections. The tanning claim almost everybody buys it for rests on three men.
| Field | Melanotan I | Melanotan II |
|---|---|---|
| What a trial gave | 16 mg in a rod placed under the skin every two monthsThe approved implant, in patients with a rare light sensitivity disease | 0.025 mg/kg, about 1.75 mg for a 70 kg adultRecommended by the 1996 phase I and used in all three later trials. Four trials, 43 men, 1996 to 2000. |
| What circulates | 1 mg a day for 10 days, then 2 mg a week, injected | 250 to 500 mcg daily to load, some to 1,000 mcg, then 500 mcg twice weekly or 250 mcg once or twice weekly |
| The gap | Lands on a studied dose | Below the studied dose |
| How long it lasts | About 30 minutes for the peptide itself on the European label, and 0.8 to 1.7 hours in the elimination phase measured after injection under the skin in three volunteers. The approved implant reads at about 15 hours in 12 healthy adults, which is the polymer doing the work rather than the peptide. | How long it lasts in a person is something I could not find. The only study of that kind that could be located was in rats, 0.3 milligrams for every kilogram of body weight given into a vein, and the half life figures printed on seller pages have no human source that could be located. |
| Route studied | As an implant under the skin in every efficacy trial: 16 mg, three implants over 180 days in the pivotal study. The injected human record is separate and older, daily dosing at 0.08 to 0.21 mg per kilogram in 1997 and 2000, ten days in 2004 and three ten day cycles in 2006, which works out at roughly 5.6 to 14.7 mg an injection for a 70 kg adult. | Under the skin, in all four human trials. The only study of how long a dose lasts was in rats, into a vein. |
| Route used | Injected under the skin at home, daily for a loading period and then weekly. Every published injection schedule I found dosed on weekdays rather than weekly, and I found no published study of a weekly injection of this peptide in people. | Injected under the skin at home, usually paired with ultraviolet light exposure. A nasal spray is also sold commercially, and no human study of melanotan II by that route was found. |
| Vial sizes | 10 mg | 10 mg |
The distance, stated
Lands on a studied dose
Melanotan I
The monthly rate matches and nothing else does. A vendor page shows its working: the trials used a 16 mg implant every 60 days, which it converts to 8 mg a month, and 2 mg a week is the same monthly figure. On a four week month those agree; across a calendar year it is 104 mg against about 97 mg. What does not carry across is the delivery. The rod releases most of its content in the first two days, is absorbed over 50 to 60 days, and is placed by a trained physician three or four times a year in Europe. A weekly injection of a peptide with a half life measured in hours produces the opposite shape. The loading figure has no study behind it either: it sits at a fifth to a tenth of the daily amounts the injected trials used, and the page that prints it says experts encourage erring on the side of safety.
Below the studied dose
Melanotan II
The convention sits below the tested amount rather than above it. The three later trials used 0.025 mg/kg, about 1.75 mg for a 70 kg adult, and the 1996 phase I ran 0.01 to 0.03 mg/kg, roughly 0.7 to 2.1 mg at that weight, so what circulates is between a seventh and a third of what anybody was given. I could not trace it to a derivation: one says the figures are extrapolated from the published research range and then names no publication, and another concedes the loading and maintenance models are community-derived.
What people get wrong
Melanotan I
The costly mistake is reading an approval for one product as an approval for another. A vendor page can point at the chemical database, point at the label, and be telling the truth about the molecule, and everything after that sentence is transferred from a rod to a vial. The approval is also thinner than the pages suggest, and both regulators say so in their own documents. One pivotal trial carried the European authorisation after two others were dropped following an inspection; the headline figure of 24 extra pain free hours across six months, and its range from 0.3 to 50.3, come from a method the assessment report says was specified after the data were in, printed under a heading for post hoc analyses; significance on the protocol primary endpoint came only on a one sided test; and seven members of the committee signed a divergent position against granting it without specific obligations.
Melanotan II
The mistake is assuming the circulating numbers came out of the research, and here they miss in the unusual direction. The three later trials used 0.025 mg/kg, about 1.75 milligrams for a 70 kilogram adult, and the 1996 first in human study ran 0.01 to 0.03 mg/kg, roughly 0.7 to 2.1 milligrams at that weight, so what circulates is between a seventh and a third of what anybody was given. It sits below the tested amount rather than above it, which is the reverse of nearly everything else in this reference. I could not trace the number to a derivation: one says the figures are extrapolated from the published research range and then names no publication for them, and another concedes in its fine print that no dose approved by the United States Food and Drug Administration exists and that the loading and maintenance models are community derived. The second mistake is what the trials were for. Four trials, 43 men, and what they measured was erections. The tanning claim, which is the reason almost everybody buys it, rests on three men who received five injections each, two of whom went darker.
Every figure above is carried across from each compound’s entry, which is where the citations live.
All 65 compounds on one page at what circulates vs what was studied, or pick another two to compare.