Melanotan II is a synthetic α-MSH analogue with the ability to bind MC1R, MC3R, MC4R, and MC5R receptors [R]. Compared to Melanotin I, it shows an ability to cross the blood-brain barrier, resulting in central nervous system effects including sexual behavior, appetite, and mood regulation. It has a shorter duration of action,
Melanotan II has documented effects on sexual arousal and erectile dysfunction because of its affinity for specific receptors in the brain [1]. By activating MC4R and MC3R, researchers found that it stimulated neural pathways involved in sexual motivation and performance, independent of direct sexual stimulation [1]. In animal studies, Melanotan II induced spontaneous erections and increased libido in both males and females [2, 3].
In a small study of men with psychological (not physical) erectile dysfunction, Melanotan-II triggered erections in most participants and kept them firm for much longer than a placebo [4]. Some men experienced mild side effects like nausea or yawning, but these were temporary and didn’t need treatment [4].
Melanotan analogs stimulate melanocytes to increase eumelanin production, leading to darker skin pigmentation [5]. While Melanotan I is highly selective for the MC1R receptor (which leads to more predictable tanning effects), Melanotan II activates multiple other receptors, which can cause broader systemic effects [6].
Melanotan II is thought to influence energy balance and appetite regulation via MC3R and MC4R activation in key regions of the brain that control hunger and satiety, the hypothalamus and nucleus accumbens [7].
In an animal study, researchers gave Melanotan II to rats and found that it caused a sharp drop in food intake over two days and significantly reduced body fat and insulin levels [8]. Even when combined with another brain chemical, neuropeptide Y, which normally increases hunger and fat storage, Melanotan II blocked most of these effects [8].
By acting on specific brain regions, melanotan II seems to reduce food intake, suppress appetite, and increase thermogenesis by activating brown adipose tissue [9].
Emerging research has suggested that melanotan II may modulate dopamine and oxytocin pathways, potentially influencing reward processing, mood, and addiction-related behaviors [10].
One study in rats found that injecting melanotan II into the bloodstream was able to activate oxytocin-producing brain cells, a hormone linked to bonding and social behavior. While it did not directly cause oxytocin release inside the brain, it increased the activity of neurons and was able to increase blood levels, suggesting it may indirectly boost levels through brainstem pathways [11].
Research Use Only. All findings described above are derived from preclinical studies (animal models and in vitro experiments). Melanotan II is not approved by the FDA for any diagnostic or therapeutic use in humans. Genesis Peptides makes no claims regarding human clinical efficacy. This product is sold exclusively for laboratory research.
Every lot undergoes five independent assays before release. Results are published in the lot-specific Certificate of Analysis.
Every lot undergoes our 4-panel testing protocol: HPLC purity analysis, ESI-MS identity confirmation, LAL endotoxin screening, and amino acid analysis (for peptides >15 residues). Full analytical data is published in the Certificate of Analysis for each lot.
Lyophilized peptides should be stored at -20°C or below for long-term stability. Once reconstituted, peptides should be stored at 2–8°C and used within a reasonable timeframe depending on the specific compound. Avoid repeated freeze-thaw cycles. Always store in a dry environment away from direct light.
Orders placed before noon PST, Monday–Saturday, ship the same day. We offer free standard shipping on orders over $150. All orders are shipped in insulated packaging with ice packs when necessary. Standard delivery typically takes 2–4 business days within the continental US.
No. All compounds sold by Genesis Peptides are strictly for in vitro and preclinical laboratory research purposes only. They are not approved for human consumption, therapeutic use, or diagnostic purposes. By purchasing, you confirm the products will be used solely for legitimate research applications.
A Certificate of Analysis (COA) is a document issued by our analytical laboratory that reports the results of all quality control tests performed on a specific lot of product. Each COA includes HPLC chromatograms, mass spectra, endotoxin results, and amino acid analysis where applicable. COAs are available in our COA Library for every lot we have shipped.
Yes. We offer volume pricing for universities, research institutions, and laboratories with recurring needs. Discounts begin at 10+ units and scale with volume. Contact our team for a custom quote tailored to your research requirements.
FOR RESEARCH USE ONLY — Products are sold exclusively for in vitro and preclinical laboratory research. Not for human consumption or administration. Not intended for diagnostic or therapeutic use. These statements have not been evaluated by the FDA.