The active ingredient is still Melanotan II, so once absorbed through the nasal mucosa, it works identically to the injectable: it binds to melanocortin receptors on melanocytes to boost melanin production, and to MC-4 receptors in the brain to heighten libido. The difference lies in delivery. The nasal route has an absorption rate of roughly 20–40% for peptides (this means not all of the peptide gets into circulation). Therefore, nasal Melanotan may require more frequent dosing or a longer loading period compared to injections to reach the same level of melanin. However, consistent use will eventually raise melanin levels in the skin. As melanin increases, the user will notice they don’t burn as easily and tan more quickly with minimal sun. The same chain of effects occurs: melanin disperses to skin cells, creating a tan and protecting underlying skin from UV damage. Meanwhile, because MT2 is systemic, users might observe the appetite and libido effects as well, although possibly less pronounced if blood levels achieved are lower than via injection. Essentially, nasal Melanotan provides a gradual, passive dosing of MT2 – absorption through the nasal membranes over time leads to a build-up of melanin production. It’s the obvious solution for those averse to injections, trading off some efficiency for convenience. The protective tan and libido enhancement mechanisms remain the same as described for Melanotan II in the injectable form.