WhatPeptide

MT-2

Melanotan II is a synthetic analog of alpha-melanocyte stimulating hormone (alpha-MSH) studied for skin tanning, erectile dysfunction, and reduced appetite through melanocortin receptor agonism. Notable for its significant side effect profile including nausea, facial flushing, and changes in existing moles. Placed on FDA Category 2 list (September 29, 2023) as 'Melanotan II.'

Moderate evidence FDA Category 2 Sexual Health

Written by WhatPeptide Editorial Team · Last updated 2026-03-17

FDA Category 2 — compounding availability may be limited.

Half-life

Approximately 30-60 minutes

Dosage range

0.25-0.5 mg subcutaneously (published protocols often describe conservative escalation)

Administration

Subcutaneous injection

Research level

Moderate

How MT-2 works

Melanotan II non-selectively activates melanocortin receptors MC1R through MC5R. MC1R activation in melanocytes increases eumelanin production causing skin darkening; MC3R and MC4R activation in the hypothalamus reduces appetite and mediates pro-erectile signaling through spinal pathways. The non-selective receptor profile compared to more targeted analogs like bremelanotide (PT-141) underlies its broader side effect burden.

Also known as: Melanotan II, Melanotan-2, MT-II

Research relevance

Sexual Health
Moderate relevance 55
Hair & Skin
Some relevance 40

Side effects & safety

Nausea Facial flushing Spontaneous erections Darkening/growth of moles Fatigue Yawning

Contraindications

History of melanoma or dysplastic nevi
Cardiovascular disease
Pregnancy
Hypertension

Consult a healthcare provider before use if any of these apply to you.

Key studies

FAQ

What is MT-2? +
Melanotan II is a synthetic analog of alpha-melanocyte stimulating hormone (alpha-MSH) studied for skin tanning, erectile dysfunction, and reduced appetite through melanocortin receptor agonism. Notable for its significant side effect profile including nausea, facial flushing, and changes in existing moles. Placed on FDA Category 2 list (September 29, 2023) as 'Melanotan II.' Its mechanism of action is supported by moderate clinical and preclinical evidence.
What is MT-2 researched for? +
MT-2 has the strongest research relevance for Sexual Health, Hair & Skin. Evidence is supported by moderate clinical and preclinical evidence.
What are the side effects of MT-2? +
Reported side effects include Nausea, Facial flushing, Spontaneous erections, Darkening/growth of moles, Fatigue, Yawning. Key contraindications: History of melanoma or dysplastic nevi; Cardiovascular disease; Pregnancy; Hypertension.
Is MT-2 FDA approved? +
MT-2 is classified as FDA Category 2, meaning compounding availability may be limited.
How is MT-2 administered? +
MT-2 is typically administered via subcutaneous route. Researched dosage range: 0.25-0.5 mg subcutaneously (published protocols often describe conservative escalation). Half-life: Approximately 30-60 minutes.

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