In plain English
Melanotan II is a lab-made version of the hormone that tells your skin to make melanin, the pigment that gives you a tan. It produces a deep tan with little sun exposure, and it also strongly boosts libido and can reduce appetite. PT-141 was developed from it.
What it's used for
- Sunless or faster tanning
- Libido and arousal
- Appetite reduction
- Interest in sun protection for very fair skin
Benefits
In small human studies at the University of Arizona, Melanotan II:
- Darkened the skin within a few doses, with little or no sun
- Produced spontaneous erections and increased desire in men
- Reduced appetite in some participants
Users report a deep, even tan with much less sun exposure, stronger libido and less hunger.
How it works
In simple terms: Melanotan II tells your skin to tan and your brain to want more.
It activates several melanocortin receptors. MC1R on skin pigment cells drives melanin production, darkening the skin. MC3R and MC4R in the brain affect sexual desire and appetite. It is much longer-lasting than the natural hormone it copies (alpha-MSH), so small doses have strong effects.
Development history
- 1980s–1990s: Developed at the University of Arizona as a possible way to tan without sun damage.
- 1990s: Strong effects on arousal were noticed in early studies, leading to the development of PT-141.
- 2000s onward: Widely used for tanning through research peptide suppliers.
Typical protocols
These ranges are what users commonly report.
| Phase | Dose | Frequency | Notes |
|---|---|---|---|
| Test dose | 100–250 mcg | Once | To check for nausea |
| Loading | 250–500 mcg | Daily or every other day | Until the desired color, often 1–3 weeks, usually with some sun or tanning bed exposure |
| Maintenance | 250–500 mcg | 1–2 times weekly | To hold the tan |
Users usually inject in the evening so nausea passes during sleep.
Cycling
Used in a loading phase until the desired tan, then low-frequency maintenance. Many users stop over winter.
Administration options
- Subcutaneous injection: most common and most predictable.
- Nasal spray: also sold, though absorption is less consistent.
Reconstitution and dosing calculator
Melanotan II usually comes in 10 mg vials and is commonly mixed with 2–3 mL of bacteriostatic water. Doses are small, so a 0.3 mL or 0.5 mL syringe makes measuring easier.
Draw your syringe to
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- Volume to draw
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- Concentration
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- Each unit holds
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- Doses per vial
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Show the math
This tool does arithmetic only. It does not choose a dose or confirm that any substance is right for you. Double-check every result against your syringe and your clinician’s instructions.
Side effects and safety
- Most common: nausea, facial flushing and lower appetite, especially with the first doses.
- Spontaneous erections in men, and yawning or stretching after a dose.
- Darkening of existing moles and freckles, and new moles. Anyone using it should watch their moles closely; changing or unusual moles should be checked by a doctor, and people with a history of melanoma should avoid it.
- Rare reports of kidney problems and raised blood pressure.
- Avoid during pregnancy and breastfeeding.
Common stacks
Users report combining it with PT-141 for libido, or using a small amount of sun or tanning bed time to speed results.
Storage
Powder: refrigerate, dry and away from light.
After mixing: refrigerate at 2–8 °C, protect from light, and use within about 4 weeks.
Compare with
- Melanotan I (afamelanotide): more selective for skin tanning, with fewer libido and appetite effects.
- PT-141: developed from Melanotan II for libido, with much weaker tanning.
Frequently asked questions
Do I still need sun?
Users report it works fastest with a little sun or tanning bed exposure, but far less than normal.
How long does the tan last?
With maintenance doses it can be held for months; without them it fades over several weeks.
Why does it make me nauseous?
Nausea is common with the first doses. Starting low and injecting at night usually helps.
What about moles?
Moles often darken. Keep an eye on them and have any that change shape, size or color checked.
References
- Dorr RT, et al. Evaluation of melanotan-II, a superpotent cyclic melanotropic peptide in a pilot phase-I clinical study. Life Sci. 1996;58(20):1777-1784.
- Wessells H, et al. Synthetic melanotropic peptide initiates erections in men with psychogenic erectile dysfunction. J Urol. 1998;160(2):389-393.