The 'Barbie drug' is back in the spotlightalong with its life threatening health risks MDLinx 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 Melanotan (MT) II Melanocortin Receptor Agonist MedChemExpress Health expert says Melanotan II darkens skin moles and can make melanoma hard to detect Herald Sun