Reviewed by Dr. Jason Wright, D.O. · September 23, 2026
The science
How it works
Mimics alpha-MSH
A synthetic version of the pigment-stimulating hormone, made cyclic so it lasts longer and binds more strongly.
Binds MC1R for pigment
Activates MC1R on melanocytes, pushing them to produce melanin.
Also hits MC3R and MC4R
It activates the arousal and appetite receptors nearly as readily as the pigment one. That is where the nausea and the sexual effects come from, and it is why PT-141 was developed from this molecule.
Potent and long-acting
The cyclic structure makes it stronger than Melanotan I, which is why it is started with a test dose.
Small early human studies showed tanning; side effects are well documented.
Dosing
Your dosing plan
Dr. Wright sets your exact dose within this range at your visit.
Test dose
FormSubcutaneous
Dose250 mcg (25 units)
ScheduleFirst use
Based onClinical convention
Loading
FormSubcutaneous, night
Dose250–500 mcg (25–50 units)
ScheduleNightly for 7–14 days
Based onClinical convention
Maintenance
FormSubcutaneous
Dose500 mcg–1 mg (50–100 units)
ScheduleOnce or twice a week
Based onClinical convention
Side effects
Side effects and what to expect
NauseaCommon · First doses
Take at night; the test dose helps.
FlushingCommon · After doses
Passes on its own.
Spontaneous erectionsCommon in men · After doses
An erection lasting over 4 hours needs the emergency room.
Darkening of moles or frecklesCommon · Weeks
Any new or changing mole needs a check.
Increased libido and spontaneous erectionsCommon · Within 1 to 2 hours of a dose
A note from Dr. Wright
Melanotan II tans faster than Melanotan I, and it brings the rest of the melanocortin effects with it: nausea, arousal, and a higher chance of pigment changes you don’t want. I screen the skin first, start with a test dose, and keep checking moles throughout.
Dr. Jason Wright, D.O. · Board certified, American Board of Cosmetic Surgery
Cost & access
Getting started with Melanotan II
Melanotan II
5 mg in a 5 mL vial (1 mg/mL) · Labeled in your name
