-Induces tanning at low doses
-Increases sexual desire and function for men and women
- Minimal or no undesirable side effects.
- Decrease body fat mass and reduce food intake
- Potent self-tanner applications.

  Melanotan II also known as PT-141 was developed by researchers at the University of Arizona College of Medicine. Melanotan II is an analog of the peptide hormone alpha-melanocyte stimulating hormone (?-MSH), this hormone provides a therapeutic tan with the ability to lower the risk of skin cancer, (MSH) also plays an important role in regulating sexual arousal in men and women. Melanotan II has the additional effect of decreasing body fat mass. Melanotan II It is a cyclic lactyam analog of alpha-MSH with the amino acid sequence Ac-Nle-cyclo[Asp-His-D-Phe- Arg-Trp-Lys]-NH2.
Melanotan II is in a class of peptide hormone known as Melanocortins (MCs). Melanocortins (MCs) are multifunctional peptide hormones that regulate a diversity of physiological functions. MCs have been implicated in sexual function in animals.
A MC analog, Melanotan II (MTII), can enhance sexual function in human males (erectile activity) and females (increased levels of sexual desire and genital arousal). Unlike other sexual-enhancement drugs, MTII works at the level of the brain, thus eliciting a rather natural sexual response with minimal or no undesirable side effects. The actions of the peptide were discovered accidentally while studying the effects of the peptide and related analogs on human skin pigmentation (tanning). Hadley ME (2005).
Melanotan II, PT-141, a cyclic heptapeptide melanocortin analog, was evaluated following subcutaneous administration to healthy male subjects and to patients with erectile dysfunction (ED) who report an inadequate response to Viagra. The erectile response induced by PT-141 was statistically significant at both doses. PT-141 was safe and well tolerated in both studies. The erectogenic potential of PT-141, its tolerability profile and its ability to cause significant erections in patients who do not have an adequate response to a PDE5 inhibitor suggest that PT-141 may provide an alternative treatment for ED with a potentially broad patient base.Rosen RC, Diamond LE, Earle DC, Shadiack AM,Molinoff PB (2004).
In addition to the sexual enhancement and tanning effects of Melanotan II, MT-II has also exhibited the potential to decrease body fat mass and reduce food intake. Choi YH, Li C, Hartzell DL, Lin J, Della-Fera MA, Baile CA (2003).
MT-II has tanning activity in humans given only 5 low doses every other day by subcutaneous injection. The recommended single MT-II dose for future Phase I studies is 0.025 mg/kg/day.
Synonym: Ac-[Nle4Asp5D-Phe7Lys10]?-MSH- (4-10)-NH2
Amino Acid Sequence: Ac-Nle-Asp-His-D-Phe-Arg-Trp- Lys-NH2
Molecular Formula: C50H69N15O9 ? xC2HF3O2
Molecular Weight: 1024.18 (free base basis)