What are the side effects of MT-2 (Melanotan II)?
The most commonly reported MT-2 (Melanotan II) side effects are nausea (more pronounced than MT-1), facial flushing, spontaneous erections / increased libido. Most are mild and tend to be dose dependent. It is generally avoided with personal history of melanoma. Human clinical evidence for MT-2 (Melanotan II) is limited, so this reflects reported and observed effects, not a complete safety profile.
Reported MT-2 (Melanotan II) side effects
- Nausea (more pronounced than MT-1)
- Facial flushing
- Spontaneous erections / increased libido
- Appetite suppression
- Mole / freckle darkening, mole-map first
- Headache
Who should avoid it
- Personal history of melanoma
- Atypical mole syndrome
- Pregnancy / nursing
References
- Evaluation of melanotan-II, a superpotent cyclic melanotropic peptide in a pilot phase-I clinical study — Dorr RT, Lines R, Levine N, Brooks C, Xiang L, Hruby VJ, Hadley ME — Life Sciences, 1996;58(20):1777-84
- Melanotropic peptides: more than just 'Barbie drugs' and 'sun-tan jabs'? — Langan EA, Nie Z, Rhodes LE — British Journal of Dermatology, 2010;163(3):451-5
Pepdex is an editorial reference, not medical advice. Peptides vary in legal and approval status by country, many are research compounds without full human safety data. Talk to a qualified clinician before starting anything.
More on MT-2 (Melanotan II)
Last updated 2026-06-06.