In sexual & aesthetic wellness, Melanotan II (MT-2) comes up for its ability to darken skin and sometimes heighten libido—but it should be framed as investigational and high-risk, not routine care. Health authorities repeatedly warn that MT-2 products sold as injections or nasal sprays are unlicensed/unapproved and often of unknown quality. Clinically, if the goal is desire rather than hemodynamics, note that centrally acting melanocortin agonism is a valid pathway—but PT-141 (bremelanotide) is the only FDA-approved agent in this class (for HSDD in premenopausal women), whereas MT-2 is not approved for any indication.
Mechanism. MT-2 is a non-selective melanocortin receptor agonist. Activation of MC1R in melanocytes boosts melanin production (tanning), while central MC3R/MC4R activity can influence sexual arousal circuitry—explaining reports of increased libido or spontaneous erections. These effects reflect the broader melanocortin system’s roles in pigmentation and sexual function.
Evidence & safety. Small human studies showed erectile responses to MT-2, but side effects were frequent (nausea, flushing, yawning, prolonged erections). Dermatology sources list mole darkening, pigment changes, and concern for melanoma risk, alongside GI effects and headaches. Consumer-market nasal sprays are specifically discouraged by hospital and dermatology groups due to unknown dose, contamination risk, and lack of safety data.
Regulatory stance. MT-2 is not FDA-approved; UK (MHRA), Ireland (HPRA), and Australia (TGA) have issued explicit warnings against its sale and use, calling it dangerous and illegal outside regulated channels. Media and regulator updates highlight a surge of unregulated “tanning sprays/drops” driven by social platforms—another reason to counsel patients toward approved options (e.g., PT-141 for HSDD) or non-drug tanning alternatives (DHA self-tanners) rather than MT-2.