Your body already makes a hormone that tells your skin to tan. Melanotan 2 is a synthetic peptide engineered to mimic that hormone but in a version that's more potent and Emerging Threat: Melanotan, Repackaging, and Online Sales Avoid nasal tanning sprays or nasal tanners entirely. These products promise an all over tan without sun exposure but they are unregulated, can be unsafe, and contain potentially risky substances like Melanotan 2. Hard Side Effect DocCheck The Last Neuroscientist Andrew Huberman warns about the dangers of Melanotan II, a synthetic tanning peptide allegedly used by Robert F Kennedy Jr, due to its potential complications and side effects. >>