Melatonin injections for tanning are based on the principle of increasing melanin production in the skin. Melanin is naturally produced by melanocytes in the skin when it is exposed to sunlight. However, melatonin injections, particularly Melanotan 2, work by stimulating these melanocytes without the need for UV exposure. Visit : https://www.trutan.net/how-to-use-melanotan-2/