Melanotan-2
aka MT-2, MT2
Melanocortin receptor agonist (skin pigmentation, libido)
Half-life
~33 minutes (short — vs MT-1 at 33 hours)
How long it stays active in your body
Dosing
Daily during loading (1–2 weeks), then weekly
How often you take a dose
Route
SubQ
How it goes into the body
Status
Research
Sold for lab research — not approved for humans
What it is
A synthetic analog of α-MSH that activates multiple melanocortin receptors (MC1R, MC3R, MC4R, MC5R). MC1R activation drives melanin production (tanning); MC4R activation drives libido (similar mechanism to PT-141). Not FDA-approved. Real expert disagreement on whether it belongs in any stack.
How it works
Non-selective melanocortin receptor agonist. MC1R → melanocyte stimulation → darker pigmentation + UV protection. MC4R → central libido enhancement. Crosses the blood-brain barrier readily — also affects appetite, mood, and erection pathways.
What the research says
Originally developed at University of Arizona for melanoma prevention. Limited human trials. Most use is recreational tanning + libido enhancement via gray-market sources. The non-selective receptor activation is the source of side-effect concerns.
Sources: PubMed: Melanotan II
Common dosing ranges
- Range
- 250–500 mcg/day loading; 0.5–1 mg/week maintenance
- Frequency
- Daily during loading (1–2 weeks), then weekly
- Duration
- Cycle until desired tan, then maintain
Sources: PubMed
Administration
Side effects
Common
- Nausea (often debilitating, especially early)
- Facial flushing
- Spontaneous erections
- Loss of appetite
- Darkening of existing moles and freckles
Serious / theoretical
- New mole formation — Dr. Jones DC reports moles taking months to disappear after cessation
- Theoretical melanoma risk (unstudied)
- Cardiovascular effects from sustained MC receptor activation
Sources: PubMed: MT-II safety
Notes
Real expert split: JD Denham + Jones DC warn against (new mole formation, short half-life); Dr. Tatem rates it S-tier (now prescription-available); Bachmeyer flags non-selective receptor activation. MT-1 (33-hour half-life) is the cleaner alternative if pigmentation is the goal. For libido alone, PT-141 is the more targeted choice.