Skin & hair · Libido
Melanotan 2, simplified.
Also called MT-II
Early researchAn unapproved tanning peptide that also affects appetite and sex drive. PT-141 was developed from it.
- Size
- 7 amino acids, cyclic
- How it is taken
- Injection or nasal spray
- Status
- Research compound
- Available sizes
- Vials: 10 mg
What is it?
Like Melanotan 1, it copies alpha-MSH, but it acts on more receptors. That is why it also causes arousal and lower appetite. Researchers turned it into PT-141 to focus on libido.
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What studies show
- In peopleSmall early studies showed tanning and erections in men.
- In peopleCase reports describe new or changing moles in people using it.
What we don’t know yet
- Long-term safety, including any link to skin cancer.
Side effects and cautions
- Nausea, flushing and unwanted erections are common.
- Health agencies in several countries have warned against it because of mole changes and unknown purity.
Is it legal?
Not approved anywhere.
Dosage & schedule evidence
How to read published schedules
Third-party protocols are not established clinical dosing standards. Safe human dose, frequency, and duration may be unknown. Research findings may not translate to safe or effective personal use.
| Measurement | Meaning |
|---|---|
| 1 mg | 1,000 mcg (mass) |
| 100 U-100 units | 1 mL (volume, not dose) |
See third-party published protocols ↗ for research context. North Star does not validate these schedules.
Consult your doctor before considering any peptide for personal use. Educational only, not administration guidance.
Common questions
What is Melanotan 2?
An unapproved tanning peptide that also affects appetite and sex drive. PT-141 was developed from it. Like Melanotan 1, it copies alpha-MSH, but it acts on more receptors. That is why it also causes arousal and lower appetite. Researchers turned it into PT-141 to focus on libido.
What does the research say about Melanotan 2?
Small early studies showed tanning and erections in men. Case reports describe new or changing moles in people using it.
Is Melanotan 2 FDA approved?
Not approved anywhere.
What are the side effects of Melanotan 2?
Nausea, flushing and unwanted erections are common. Health agencies in several countries have warned against it because of mole changes and unknown purity.
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This page explains published research in plain language. It is not medical advice, a diagnosis, or a recommendation to take anything, and it does not give dosing. Most peptides here are not FDA-approved, and products sold online vary widely in purity. Rules around peptides are changing, so check the current status and talk with a licensed clinician before starting anything. Last reviewed 2026-10-19.