Nasal Tanners Say "NO WAY" to the spray! UNAPPROVED, UNREGULATED, UNSAFE. Nasal tanning sprays, or nasal tanners, promise an all over tan without sun exposure. However, they are unregulated, can be Melanotan II Skin Pigmentation & Libido 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 Health expert says Melanotan II darkens skin moles and can make melanoma hard to detect Herald Sun Melanotan II (Tan Jabs): Why They're Not Worth The Risk