Looks · part of Skin, hair and appearance
Does it actually tan you?
Melanin density measured on the skin, which is one of the few cosmetic endpoints that is objective.
44
people in trials
4
studies in people
0
compounds, animal or lab only
1
compounds people report on
1
trials found nothing
Measured in people
A trial that gave people the compound comes first. A study that only watched people, who happened to have more or less of something related, comes after. Both are studies in people and both are here. Only the first kind tested the thing you are asking about, and the watch-only ones are labelled. Within that, the most people come first. That is a fact about the studies, not a judgement about the compound. Counts are never added up across compounds, because the same person can be in more than one trial.
Peptides and blends
4 compounds · 44 people given one of themWhat this archive is for. Trials of the compound come first, ranked by how many people were actually given it. Studies that only observed people are below them and labelled.
- 01GonadorelinPeptideModerate. At least one finished study in people, and at least 100 people who took it. 3 completed trials, 110 people given it.8 reported28 people given it1 trial
The pump got sperm going sooner, but no more men got there in the end. 28 men producing no sperm were compared: 10 wore a gonadorelin pump and 18 took the usual hormone injections. Nobody was assigned by chance, so the groups were not built alike. First sperm appeared at about six months on the pump against fourteen on injections. By the end roughly nine in ten succeeded either way, a gap too small to call. Skin redness and hardening at the pump site was common.
The numbers Nonrandomized comparison in 28 azoospermic men: 10 on a pulsatile gonadorelin pump and 18 on cyclical hCG and hMG. Median time to first spermatogenesis 6 against 14 months (p=.01), but the eventual rates, 90 percent against 83.3 percent, differed significantly in neither the superiority nor the non-inferiority test. Allergic skin erythema and scleroma at the infusion site was a common pump side effect. The authors declared no conflicts.
American Journal of Men's Health, 2019· 28 people
- 02GHK-CuPeptideLimited. People have taken it in a published study, but fewer than 100 of them. 2 completed trials, 99 people given it.7 reported13 people given it1 trial1 found nothing
found nothingNothing an outside observer could measure got better. 13 patients had laser resurfacing around the mouth, then were assigned at random to a skincare routine with or without GHK-Cu. Judges who did not know which patient got which, plus computer image analysis, found no difference in redness, wrinkles or overall skin quality. The only thing that favoured the copper peptide was the patients' own satisfaction rating. Thirteen people is a very small test.
The numbers 13 patients randomized after circumoral CO2 laser resurfacing to a skincare regimen with or without GHK-Cu. Computer analysis and blinded evaluators found no significant difference in erythema resolution, wrinkles or overall skin quality. Only the patients' own questionnaire favoured GHK-Cu, at P = 0.04.
Archives of Facial Plastic Surgery, 2006· 13 people
- 03Melanotan IIPeptideStrong. At least two finished studies in people, and at least 1,000 people who took it. 5 completed trials, 1,310 people given it.9 reported3 people given it1 trial
The first look at this compound in people was tiny, and the side effect it turned up became the reason people buy it. Three male volunteers took shots under the skin for two weeks. Their skin darkened, which was the point. Most doses made them feel sick, and the highest left them drowsy and tired. They also got spontaneous erections lasting one to five hours. Three people cannot tell you how common any of that is, or whether the compound is safe.
The numbers Three male volunteers dosed subcutaneously for two weeks: increased pigmentation, mild nausea at most doses, somnolence and fatigue at 0.03 mg/kg, and spontaneous penile erections lasting 1 to 5 hours after dosing.
Life Sciences, 1996· 3 people
- 04RusfertidePeptideModerate. At least one finished study in people, and at least 100 people who took it. 5 completed trials, 166 people given it.0 people given it1 trial
This study measured what the body does with rusfertide, not whether it helps anyone. Healthy adults took a range of doses, each person trying more than one, and everybody knew what they were getting. Peak levels arrived a day after the smaller doses and within hours after the larger ones. The body took anywhere from under a day to over two days to clear half of it. Iron in the blood fell in step with the dose. Redness and itching at the injection site were common.
The numbers Randomised open-label crossover in healthy adults, 10 to 60 mg. Median time to peak 24 hours at 10 to 30 mg and 2 to 4 hours at 45 to 60 mg; mean terminal half-life 19.6 to 57.1 hours; dose-related falls in serum iron and transferrin saturation. Injection site erythema and pruritus were the treatment-related adverse events in 10 percent or more.
Drugs in R and D, 2024· number of people not given
What people using these actually report
These are people describing their own use. They come from clinic write-ups, complaint records kept by regulators, and public forums, and they are shown as written. They are the best guide on this page to what people actually do, what they expect, and what goes wrong. They cannot show that anything works. Nobody was compared with people on a dummy pill, and people who saw no effect mostly stopped posting. Both things are true at once. The bad reports are kept in for the same reason.
- The comparison people make is that this one is described as slower to produce visible tanning and as having a narrower side effect profile, the reasoning offered being that it does not reach the brain the way the cyclic version does. That reasoning is actively disputed in the same forums, with posters pointing out that it acts on more targets in the body than the marketing implies, and that this hormone system is not well understood.
Sources: Melanotan comparison and safety threads on Bluelight, and melanocortin threads on ExcelMale, found by site-restricted search and read in September 2026. Nothing above is attributed to any specific post and no post is reproduced.
Why the trial record looks like this
A missing trial usually means nobody would pay for it. Nobody spends hundreds of millions of dollars on a molecule they cannot own. So the compounds with the thinnest record in people are often the oldest and easiest to get, not the weakest. Taking Gonadorelin as the example, because it states the problem most clearly:
Who paid, and when, explains this record. Pulsed gonadorelin was worked out in university hormone clinics in the 1970s and 1980s, mostly with public money. The question was a rare one: how to bring on puberty and fertility in people born without the brain signal that starts them. The research answered it well, but the answer needed a pump. That is a device business, not a blockbuster drug. The patients are few, the treatment is fiddly, and the alternative, hCG and hMG shots, is cheaper to give. The brand-name products mostly went away. The drug lived on through compounding pharmacies, which is what this page's legal status reflects.
The market today is a different one. Testosterone clinics sell gonadorelin as an add-on, injected two or three times a week. The idea is that keeping the body's own LH and FSH signals flowing keeps the testicles full size and fertile. No company could pay for the study that would test that. A compounded batch of an old peptide nobody can own brings no exclusive sales, so nobody can earn back the cost. The clinics that prescribe it have no legal duty to run one. So the evidence sits where public money left it forty years ago, aimed at a different question.
The real disagreement is whether the old evidence carries over. The pump studies showed that the pituitary responds to well-spaced pulses and shuts down under a steady supply. That same effect is why leuprolide, a drug in this family, is used to switch hormones off. Prescribers argue that a short-acting shot two or three times a week is closer to a pulse than to a steady supply, and that the testicles stay full size in practice. Critics argue that a shot every few days is neither a pulse nor a steady supply. They point out that nobody has measured LH, FSH or testosterone inside the testicle on that schedule in men on testosterone. And hCG, which skips the pituitary altogether, has a better-studied path to the same goal. That question is open, and the study that would settle it has nobody to pay for it.
A compound shows up here only when a study on its own page names this goal and reports a result for it. Just naming it is not enough. Work in people, in animals and in the lab is counted separately and never mixed. People counts come from the study lines, and when in doubt they count low. Nothing here is advice. Nothing here tells you to take or to avoid anything.