Melanotan II vs PT 141: Key Differences in Research Why Are People Injecting Themselves with Peptides? The New Yorker Melanotan II A Sun Kissed Look, and a Confident You. Viral 'Barbie drug' for tanning can cause brain swelling and even cancer, experts warn Melanotan (MT) II Melanocortin Receptor Agonist MedChemExpress Nasal tanners claim to work by using Melanotan II, a chemical that darkens skin pigmentation. It is illegal to sell medicinal products containing Melanotan II in the UK but since the tanners are sold