Home / Peptides

Melanotan II

Also called: Melanotan-2, MT II, MT2

By The Health Stacks Research TeamUpdated July 27, 2026

Melanotan II is a lab-made substance that acts like a natural hormone in your body. It belongs to a group of substances called melanocortins. People use it because they want to get a darker skin tan without being in the sun.

Some people also use it because it can change how hungry they feel and boost their interest in sex.When this substance enters the body, it turns on switches in the brain and skin. In the skin, these switches tell the cells to make more dark pigment, which causes tanning. In the brain, it turns on switches that control sexual desire and appetite.

Because it works directly on the brain, it is used to help with sexual function problems.There is still a lot we do not know about how safe this substance is for humans. It is not approved by the Food and Drug Administration (FDA), which means doctors cannot prescribe it legally in the United States. Users have reported side effects like feeling sick to their stomach, skin spots, and other health problems. Because it is mostly sold online for research only, anyone using it takes on serious health risks.

Research-stageEarly-stage — studied in cell or animal models, not yet tested in humans. Low confidenceBelow 40 — limited or lower-quality sourcing. Verify independently before relying on this.
Where to Source Melanotan II
Tested purity COA available Fast shipping

What Melanotan II Helps With

The benefits people report — backed by research.

Reproductive & hormonal (9)

Erectile dysfunction treatment 65/100· 2 srcIncreases sexual desire and causes spontaneous erections 85/100Significant efficacy in treating erectile dysfunction 80/100Initiates spontaneous erections in erectile dysfunction 75/100Increases libido 70/100Increases sexual desire 70/100Triggers spontaneous erections and central sexual arousal 70/100Increased sexual arousal 65/100Increases sexual desire and libido 65/100

Neuroprotection & cognitive (5)

Neuroprotection in ischemic and excitotoxic models via MC4R 85/100Supports brain health 85/100Improvement in hippocampal synaptic plasticity and spatial memory 85/100Modulation of dopaminergic circuitry and protection in Parkinson's model 85/100Autism Symptom Reduction 65/100

Skin, hair & cosmetic (3)

Improves skin health 85/100Stimulates melanin production with minimal UV exposure 75/100Stimulates melanin production 60/100

Other Benefits (2)

Reduces inflammation 85/100Appetite Control 70/100
Melanotan II — weight loss

Get Melanotan II for Your Research

Compare research-grade suppliers with third-party COAs and published purity data. For in-vitro and laboratory research use only — not for human consumption, diagnosis, or treatment.

Find Melanotan II Research Suppliers
Tested purity COA available Fast shipping
Technical Details & Research (click to expand)

Mechanism of Action

Melanotan II is a synthetic cyclic heptapeptide and non-selective melanocortin receptor agonist (MC1R/MC3R/MC4R/MC5R). MC1R agonism darkens skin (tanning); MC4R effects increase libido and induce erections. It is NOT approved by the FDA/TGA/EMA and is sold illicitly; regulators warn against use due to significant safety risks.

Known Side Effects

Research Citations (15)

  • TGA warning: tanning products containing melanotan

    Guideline2023 Key study 70/100
    Source

  • Melanotan-induced priapism: a hard-earned tan

    CaseReport2019 60/100
    Source

  • Melanotan [Melanotan]

    90/100
    Source

  • Melanocortin peptide therapeutics: historical milestones, clinical studies and commercialization

    90/100
    Source

  • Effects of a superpotent melanotropic peptide in combination with solar UV radiation on tanning of the skin in human volunteers

    90/100
    Source

  • Evaluation of melanotan-II, a superpotent cyclic melanotropic peptide in a pilot phase-I clinical study

    90/100
    Source

  • Melanocortin receptor agonists, penile erection, and sexual motivation: human studies with Melanotan II

    90/100
    Source

  • Melanotan-II: Investigation of the inducer and facilitator effects on penile erection in anaesthetized rat

    90/100
    Source

  • Melanotan-II reverses autistic features in a maternal immune activation mouse model of autism

    90/100
    Source

  • Eruptive melanocytic naevi following melanotan injection

    90/100
    Source

  • Wessells et al., Int J Impot Res (2000) Phase II trial for ED, 0.025mg/kg dosing, efficacy

    85/100
    Source

  • Dorr et al., Photochem Photobiol (1996) Phase I clinical study of MT-II, melanotropic activity

    85/100
    Source

  • Hadley & Dorr, Peptides (2005) Discovery of melanocortin regulation of sexual function

    80/100
    Source

  • Hadley & Dorr, Peptides (2006) Melanocortin peptide therapeutics milestones

    80/100
    Source

  • Safarinejad, J Sex Med (2008) Bremelanotide salvage of sildenafil failures, RCT

    85/100
    Source

Free: The Peptide Stack Cheat-Sheet

The most-used peptide combinations, dosing at a glance, and what the research says — one page, one email.

No spam. Unsubscribe anytime.

Related on The Health Stacks

Compare

Melanotan II vs Bremelanotide