Melanotan 2 is an unregulated, unsafe substance often advertised as a self tanning aid., Use of Melanotan 2 has been linked to serious side effects including loss of vision, moles, stroke, muscle Melanotan 2 Pigmentation pathways, Appetite regulation Research Lets look at sunless tanning, ., Firstly theres the injections and nasal sprays which typically have an active ingredient called melanotan. This is a synthetic compound that stimulates the Melanocortin Erectile Dysfunction: Pathways, Research, and What Actually Matters