Melanotan II vs PT-141
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
PT-141 is the one with an approval and the approval does not cover the person buying it. Its 1.75 mg is lifted off the Vyleesi label, where it is the approved dose for premenopausal women, and that same label's Limitations of Use name men as a group the drug is not indicated for; against the only published male doses, 4 mg and 6 mg, the convention runs about a third to a half. Melanotan-II is a separate molecule, and the published sources cannot agree whether it is this one's parent or merely its lookalike, which is why its harm reports are not carried across.
| Field | Melanotan II | PT-141 |
|---|---|---|
| What a trial gave | 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. | 1.75 mg under the skin, in premenopausal womenTwo phase 3 trials, NCT02333071 and NCT02338960, in 1,267 premenopausal women. The only published male efficacy doses under the skin were 4 mg and 6 mg, in men sildenafil had not helped. |
| What circulates | 250 to 500 mcg daily to load, some to 1,000 mcg, then 500 mcg twice weekly or 250 mcg once or twice weekly | 1.0 to 2.0 mg under the skin in men, reported as convention |
| The gap | Below the studied dose | Lands on a studied dose |
| How long it lasts | 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. | This entry gives no figure for how long it lasts in the body. The only timing anywhere in the record is on the approved label, which describes a dose taken at least 45 minutes before anticipated sexual activity, at most one dose in 24 hours, with more than eight in a month not recommended, and which instructs prescribers to discontinue after 8 weeks if the patient does not report an improvement. |
| Route studied | Under the skin, in all four human trials. The only study of how long a dose lasts was in rats, into a vein. | Under the skin, by autoinjector into the abdomen or the thigh, in premenopausal women. In men, the only published efficacy data under the skin is a 2004 study, and the rest of the male work was given up the nose. |
| Route used | 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. | Injected under the skin, 30 to 60 minutes before sexual activity according to vendor, clinic and protocol pages, which also describe a smaller first dose before the full one. The approved product is given by autoinjector, while what men are described as holding is a vial. |
| Vial sizes | 10 mg | 10 mg |
The distance, stated
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.
Lands on a studied dose
PT-141
The number matches, and unusually for this reference it is traceable. The 1.75 mg was lifted off the Vyleesi label, where it is the approved dose for premenopausal women and the top of a phase 2b trial that compared 0.75, 1.25 and 1.75 mg in 327 of them. That same label's Limitations of Use name men as a group the drug is not indicated for. No male dose-finding study supports the number, I could not find a published trial of any design giving a man the 1.75 mg subcutaneous dose, and against the only published male subcutaneous efficacy doses, 4 mg and 6 mg, the convention runs at roughly a third to a half.
What people get wrong
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.
PT-141
The costly mistake is reading the approval as covering the person who bought it. The 1.75 mg figure is not a male number at all. It is the dose approved for premenopausal women, itself the top of three amounts, 0.75, 1.25 and 1.75 mg, compared in 327 premenopausal women in an earlier trial, and it was lifted off a label whose Limitations of Use name men as a group the drug is not indicated for. No male dose-finding study supports it, and I could not find a published trial of any design that has given a man that dose. The second mistake follows the first, which is assuming the thing being bought is large. In the trials, desire rose 0.35 points on a questionnaire and the distress item fell 0.33 points against the dummy injections, the number of satisfying sexual events did not differ significantly between the groups, and in the 52 week extension, where the drug was free and nobody was on a dummy, 684 women enrolled and 272 finished. The third is melanotan II, a separate molecule whose harm reports do not carry across, and which the published sources cannot agree is either this compound's parent or merely its lookalike.
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.