Melanotan II for Libido: What the Evidence Shows
What human and animal studies show about Melanotan II for libido, how strong that evidence is, and what is still unproven.
- Strongest evidence
- Human RCT
- Human studies
- 1
- with an outcome for libido, in our evidence file (PubMed search, 2 Oct 2026)
- Animal studies
- 1
- with an outcome for libido, in our evidence file (PubMed search, 2 Oct 2026)
- Studies we summarised
- 2
- with an outcome for libido
Evidence for libido
Each row is an outcome related to libido from a published study, strongest design first. Animal and cell results are labelled and are not human results. User reports are not counted as evidence here.
| Outcome | Result | Study type | Source |
|---|---|---|---|
| Erection without sexual stimulation | 17 of 20 men had penile erection without sexual stimulation. | Human controlled trialn = 20 | International journal of impotence research 2000, PMID 11035391 |
| Sexual desire | Increased desire after 13/19 (68%) MT-II doses vs 4/21 (19%) placebo (P<0.01). | Human controlled trialn = 20 | International journal of impotence research 2000, PMID 11035391 |
| Proceptive sexual behaviour | Both doses increased hops/darts and ear wiggling in hormone-primed female rats; pacing and lordosis unchanged. | Animal · rat (not a human result)n = 14 | Pharmacology, biochemistry, and behavior 2006, PMID 17113634 |
Melanotan II and libido are not in our PubMed count ledger yet; the rows above come from our evidence file (PubMed search, 2 Oct 2026). Grades follow our .
How strong is it?
A human randomized trial outweighs any number of animal studies. Animal and cell results show a mechanism worth testing, not that it works in people.
The sexual-health topic this page sits under
MedlinePlus notes that a number of disorders can affect the ability to have or enjoy sex in both men and women.[3]
What human studies measured that is closest to libido
The erectile-dysfunction study dosed 20 men with psychogenic and organic ED in a double-blind, placebo-controlled crossover design and monitored penile rigidity.[1]
Men in that study had a mean of 41 minutes of tip rigidity above 80% on the monitor.[1]
In the 3-volunteer pilot, a stretching and yawning complex correlated with spontaneous penile erections that lasted 1 to 5 hours after dosing.[4]
Women and animal data
In female rats primed with estradiol and progesterone, both doses of melanotan II increased hops, darts and ear wiggling; with estradiol alone there was no effect. This is rat data.[2]
The cached human libido studies enrolled men (20 with erectile dysfunction, 3 normal volunteers), so the count of human studies in women is 0 and no result for women is claimed.
Calculated from human studies in men 2; men enrolled 20, 3; human studies in women 0. Formula: studies in women = 0 among the cached human studies
Safety wording attached to the same studies
In the ED study, 12.9% of subjects had severe nausea at 0.025 mg/kg, and nausea and yawning were frequent.[1]
The priapism case report was diagnosed as low-flow and managed with cavernosal aspiration, irrigation and phenylephrine; erectile function had not yet recovered at follow-up.[5]
Other peptides people research for libido
Common questions
Does Melanotan II help with libido?
The strongest study we summarise for libido is human rct evidence, across 2 studies with an outcome for libido. A trial result is not an approval; see the legal status.
Is Melanotan II approved for libido?
No. Melanotan II is not FDA approved for any use, including libido.
Does melanotan 2 work for ED?
The ED study concluded that melanotan II is a potent initiator of penile erection in men with erectile dysfunction and called for further investigation; it is not an approved treatment.[1]
Does MT2 increase sex drive?
In the 20-man ED study, increased desire followed 13 of 19 doses (68%) of melanotan II against 4 of 21 doses (19%) of placebo.[1]
More on Melanotan II
Sources
- 1Melanocortin receptor agonists, penile erection, and sexual motivation: human studies with Melanotan II.International journal of impotence research · 2000PMID 11035391Accessed 2 Oct 2026
- 2The melanocortin agonist, melanotan II, enhances proceptive sexual behaviors in the female rat.Pharmacology, biochemistry, and behavior · 2006PMID 17113634Accessed 2 Oct 2026
- 3Official web pageOfficial web page · web page
- 4Evaluation of melanotan-II, a superpotent cyclic melanotropic peptide in a pilot phase-I clinical study.Life sciences · 1996PMID 8637402Accessed 2 Oct 2026
- 5Melanotan-induced priapism: a hard-earned tan.BMJ case reports · 2019PMID 30796078Accessed 2 Oct 2026
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