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Sexual Health / Aesthetics

Melanotan II

MT-II · "the Barbie peptide"
cautionpopularsubQ injection

What it is

Melanotan II is a synthetic analog of α-MSH (alpha-melanocyte-stimulating hormone). Originally developed at the University of Arizona as a sunless tanning agent, but turned out to also strongly increase libido (this side effect led to the development of PT-141). Not FDA-approved.

How it works

Activates melanocortin receptors throughout the body. MC1R activation in the skin stimulates melanin production (tan). MC3R/MC4R activation in the brain affects appetite (suppression) and sexual function (libido increase). Crosses blood-brain barrier.

Benefits

Timeline

Day 1–3
Loading phase. Some nausea/flushing.
Week 2–4
Visible tanning starts (with brief sun exposure).
Month 1–3
Maintained tan; effects on libido throughout.

Dosing & titration

Loading dose0.25–0.5 mg subQ daily for 1–2 weeks
Maintenance0.25–1 mg, 1–3x weekly after tan reached
When to titrate upStart very low to avoid nausea. Don't exceed 1 mg per dose.

Side effects & risks

Skin check required. Get a baseline dermatologist exam before starting and re-check annually. Any new or changing moles need evaluation.

Typical price

$60–$120/mo10 mg vial from a research/compounding source. Not FDA-approved.

Studies

Educational reference only. Not medical advice.