afamelanotide comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2025-08-08. Numbers and descriptions here follow the published literature rather than marketing material.
Published human data come mostly from small, short studies rather than large controlled trials. Reported outcomes include increased skin pigmentation and, in some reports, effects on appetite and libido, but sample sizes are small and follow-up is limited. Whether long-term use produces durable pigment changes or adverse effects is not established. Because products sold outside pharmacies are not standardized, the actual content of any given vial is often unknown. Independent testing of such material is uncommon.
Melanotan II is a synthetic cyclic heptapeptide analog derived from the core sequence of alpha-melanocyte-stimulating hormone. Researchers at the University of Arizona synthesized it during the 1980s while studying pigmentation and appetite signaling. The compound is not an approved medicine in any major jurisdiction and appears mainly in laboratory and research-chemical settings. Its structure incorporates a lactam bridge between side chains, which constrains the ring and slows enzymatic breakdown relative to the natural hormone.
Melanotan II binds several melanocortin receptor subtypes rather than a single target. MC1R on melanocytes drives melanin synthesis, while MC3R and MC4R participate in energy balance, appetite, and sexual response pathways. This lack of selectivity explains why reported effects extend beyond skin darkening. Substitutions at positions four and seven, including norleucine and D-phenylalanine, increase potency and resistance to peptidases. Understanding which receptor mediates which effect remains an active area of investigation.
Because the substance circulates mainly through informal markets, verification is a recurring theme in technical discussion. Independent analyses have found that labeled content and actual content can diverge, and that purity varies between samples. Analytical laboratories use reversed-phase chromatography to separate components and mass spectrometry to confirm identity. Isotope-labeled internal standards improve quantification in complex matrices. Such methods describe what a sample contains but say nothing about its sterility, lawful status, or suitability for any use. Open questions remain about how consistently testing is applied across the supply chain.
Regulatory treatment of this peptide varies by country. It holds no marketing authorization as a medicine in the United States, the European Union, or most other jurisdictions. Some countries classify products containing it as prescription-only or unlicensed medicines, which restricts lawful supply. Authorities have issued public notices warning that unregulated products may contain undeclared or incorrect ingredients. The molecule also appears on prohibited lists for competitive sport. These measures address supply oversight rather than any approved therapeutic role.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic cyclic heptapeptide | Analog of alpha-melanocyte-stimulating hormone |
| Primary receptor family | Melanocortin receptors MC1R through MC5R | Binding is not subtype-selective |
| Development period | 1980s | Synthesized during pigmentation and appetite research |
| Regulatory status | Not an approved medicine | No major regulator has authorized human use |
| Related compound | Afamelanotide | Linear analog studied for photoprotection |
Receptor-binding studies classify melanotan II as a non-selective melanocortin agonist. It interacts with MC1R, MC3R, MC4R and MC5R, with reported affinities in the low nanomolar range and no strong subtype preference. Activation of MC1R on dermal melanocytes shifts pigment synthesis toward eumelanin, the dark polymer deposited in melanosomes and transferred to keratinocytes. Because the same peptide engages MC4R in the hypothalamus, it also appears in animal work on food intake and erectile response, which is why it is discussed in both pigment and metabolic research. Which receptor populations dominate after systemic exposure in humans is not fully established.
Published pharmacokinetic information is limited and comes mainly from small studies rather than registrational trials. Plasma half-life is usually described as short, on the order of tens of minutes, followed by rapid tissue distribution and clearance of the intact peptide. Metabolites and low concentrations of parent compound have been reported in urine, a detail relevant to anti-doping and forensic testing. Whether repeated exposure changes receptor sensitivity or clearance over time remains an open question. Values differ noticeably between analytical assays, so published numbers should be read as approximate rather than definitive.
Melanotan II is a synthetic cyclic heptapeptide with the sequence Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2, corresponding to a molecular formula of C50H69N15O9 and a monoisotopic mass near 1024 daltons. It was designed as a structural analogue of alpha-melanocyte-stimulating hormone, a peptide hormone produced by cleavage of proopiomelanocortin. A lactam bridge between the aspartate and lysine side chains closes the ring, and the C-terminal amide removes a free carboxyl group. Both modifications increase resistance to enzymatic degradation compared with the linear parent hormone. Four substitutions distinguish it from afamelanotide, the linear analogue studied under the name melanotan I.
Solid peptide material is generally stable when kept cold and dry. Common practice is storage at -20 degrees Celsius or lower, with desiccant and protection from light. Repeated freeze-thaw cycles and exposure to moisture are associated with degradation, aggregation, or loss of material. Once dissolved, stability depends on solvent, concentration, and temperature, and solutions are usually treated as short-lived unless stability data support longer periods. Handling notes typically emphasise minimising time at ambient temperature.
Identity and purity are assessed with chromatographic and mass spectrometric techniques. Reversed-phase high-performance liquid chromatography separates the target peptide from related impurities and degradation products, and the resulting retention time is compared against a reference standard. Mass spectrometry, often coupled to liquid chromatography, confirms molecular mass. Amino acid analysis or peptide mapping can provide additional sequence-level confirmation when required. Results are only as reliable as the reference materials used alongside them.
=== 1980s to 2000s: International Expansion === In 1987, Whirlpool began selling compact washers in India and acquired a majority interest in Inglis of Canada. In 1988, Whirlpool bought a 53% stake in the large-appliance division of Philips N.V., creating a joint venture called Whirlpool International. The purchase made Whirlpool the world's largest manufacturer of major appliances, with annual sales of approximately $6 billion. The remaining 47% stake was purchased from Philips in 1991, completing the acquisition. In 1989, Whirlpool acquired the Roper brand and Bauknecht of Germany. Whirlpool entered the Indian market in the late 1980s as part of its global expansion strategy. It founded a joint venture with the TVS Group and established the first Whirlpool manufacturing facility in Puducherry, where it manufactured washing machines. In 1995, Whirlpool acquired Kelvinator India Limited, marking an entry into the refrigerator market as well. That same year, the company acquired major shares in TVS joint venture, and in 1996, the Kelvinator and TVS acquisitions were merged to create Whirlpool of India Limited. This expanded the company's portfolio on the Indian subcontinent to include washing machines, refrigerators, microwave ovens, and air conditioners. Whirlpool of India Limited is headquartered in Gurgaon, and it owns three manufacturing facilities at Faridabad, Puducherry and Pune. The Pune opened most recently, in 2022. In 1997, the company acquired a majority stake in Embraco, a Brazilian maker of compressors for refrigeration.
In June 2011, the twelfth edition of the National Toxicology Program (NTP) Report on Carcinogens (RoC) changed the listing status of formaldehyde from "reasonably anticipated to be a human carcinogen" to "known to be a human carcinogen." Concurrently, a National Academy of Sciences (NAS) committee was convened and issued an independent review of the draft US EPA IRIS assessment of formaldehyde, providing a comprehensive health effects assessment and quantitative estimates of human risks of adverse effects.
=== Reducing risk of cancer === According to the American Cancer Society, "There is growing evidence that eating traditional soy foods such as tofu may lower the risk of cancers of the breast, prostate, or endometrium (lining of the uterus), and there is some evidence it may lower the risk of certain other cancers." There is insufficient research to indicate whether taking soy dietary supplements (e.g., as a pill or capsule) has any effect on health or cancer risk. As of 2018, rigorous dietary clinical research in people with cancer has proved inconclusive.
butyl The alkyl functional group derived from either of the two isomers of butane, with the generic chemical formula –C4H9. It may occur as a substituent in organic compounds or exist independently as an ion or radical. In IUPAC nomenclature, the presence of a butyl substituent is indicated with the prefix butyl in the name of the compound, or with the abbreviation Bu in chemical formulae; e.g. butyl alcohol (butanol), which may occur in any of five different isomeric forms depending on the arrangement of the four carbon atoms, is often written with the generic formula CH4CH9OH or BuOH.
Founder, Professionals with Alzheimer's. For services to Charity. Kenneth Salter. For services to the community in Ellesmere Port, Cheshire. Cheryl Anne Sanderson. For services to Cancer Patients in Barnsley, South Yorkshire. David Saunders. For services to the community in Middlesbrough, North Yorkshire. Annie Groat Scott. For services to the community in Westray, Orkney. Pamela Mary Joyce Scull (Pamela Wingfield). Founder Principal, Wingfield School of Ballet and Dance. For services to Dance and to the community in Bristol. Sanjay Shambhu. Councillor, South Gloucestershire Council and Chair, BAME Conservatives. For Political Service. John Frederick Sharman. For services to the community in Peterborough, Cambridgeshire. Janice Sheward. Director, Cancer United. For services to People with Cancer in West Sussex. Darren Keith Sims. Founder, Daz's Rock 4 Charity. For Charitable Fundraising for Disabled and Disadvantaged Young People. Ian Robert Skinner. For services to the community in Sidmouth and the Sid Valley, Devon. Angela Ann Smith. Lately Deputy Manager, Process Controls Team, Defence Business Services. For services to Defence and to Charity. Carl Smith. Advanced Paramedic in Critical Care, East of England Ambulance Service NHS Trust, Head, Clinical Development for Emergency and Critical Care, College of Paramedics and Firefighter, Norfolk Fire and Rescue Service. For services to the NHS and to Fire and Rescue. Cheryl Barbara Smith. Leader, Girlguiding Cornwall. For services to Young People. John Alexander Alister Smyth.
Sources: en.wikipedia.org
Clinical pathology is a medical specialty that is concerned with the diagnosis of disease based on the laboratory analysis of bodily fluids, such as blood, urine, and tissue homogenates or extracts using the tools of chemistry, microbiology, hematology, molecular pathology, and Immunohaematology. This specialty requires a medical residency. Clinical pathology is a term used in the US, UK, Ireland, many Commonwealth countries, Portugal, Brazil, Italy, Japan, and Peru; countries using the equivalent in the home language of "laboratory medicine" include Austria, Germany, Romania, Poland and other Eastern European countries; other terms are "clinical analysis" (Spain) and "clinical/medical biology (France, Belgium, Netherlands, North and West Africa).
=== Discontinued === Alprazolam inhalation (AZ-002; FNP-002; Staccato® alprazolam; STAP-001; UCB-7538) – GABAA receptor positive allosteric modulator and benzodiazepine [7] Alprazolam intranasal (Panistat) – GABAA receptor positive allosteric modulator and benzodiazepine [8] BTG-1640 (ABIO-08/01; ABIO-0801) – undefined mechanism of action [9] Eglumetad (Eglumegad; LY-354740) – metabotropic glutamate mGlu2 and mGlu3 receptor agonist [10] JNJ-19567470 (CRA-5626; R-317573) – corticotropin releasing factor receptor 1 (CRF1R) antagonist [11] Nefazodone (BMY-13754; Dutonin; MJ-13754; MS-13754; Nefadar; Serzone) – serotonin 5-HT1A receptor ligand, serotonin 5-HT2A and 5-HT2C receptor antagonist, α1- and α2-adrenergic receptor antagonist, weak serotonin–norepinephrine–dopamine reuptake inhibitor (SNDRI), and other actions [12] Xenon (NBTX-001) – ionotropic glutamate NMDA receptor antagonist [13]
Bicalutamide acts as a highly selective competitive silent antagonist of the androgen receptor (AR) (IC50Tooltip half-maximal inhibitory concentration = 159–243 nM), the major biological target of the androgen sex hormones testosterone and dihydrotestosterone (DHT). It has no capacity to activate the AR under normal physiological circumstances. In addition to competitive antagonism of the AR, bicalutamide has been found to accelerate the degradation of the AR, and this action may also be involved in its activity as an antiandrogen. The activity of bicalutamide lies in the (R)-isomer, which binds to the AR with an affinity that is about 30-fold higher than that of the (S)-isomer. Levels of the (R)-isomer also notably are 100-fold higher than those of the (S)-isomer at steady-state. In terms of relative binding affinity (RBA) for the AR, bicalutamide has shown 0.29 to 6.4%, hydroxyflutamide 0.20 to 1%, flutamide <0.0057%, nilutamide 0.9%, and cyproterone acetate 2.2 to 7.8% of that of metribolone (100%) or DHT (100%) in different studies.
=== GLP-1 receptor agonists and cardiovascular risk reduction === McGuire's research has been instrumental in establishing GLP-1 receptor agonists (GLP-1 RAs) as a cornerstone of therapy for reducing cardiovascular risk in persons with type 2 diabetes. He has held leadership roles in numerous CVOTs of GLP-1 receptor agonists (GLP-1 RAs). The results of thes trials in aggregate showed that GLP-1 RAs reduce the risk of MACE (cardiovascular death, non-fatal myocardial infarction, non-fatal stroke) in people with type 2 diabetes.
Sources: en.wikipedia.org
And, another study reported that the level of FFAR2 messenger RNA in circulating blood monocytes was elevated in humans with gout compared to those who did not have gout and rose further during flare-ups of their disease; the study suggested that FFAR2 is involved in triggering gout flare-ups. Notably, a study based on the premise that FFAR2 promotes inflammation examined the effect of GLPG0974, a potent allosteric antagonist inhibitor of FFAR2, on patients with the inflammatory disease ulcerative colitis. The study progressed through phase I and II clinical studies that found the drug to be safe (i.e., non-toxic) but ineffective in reducing mild to moderate ulcerative colitis (further development of GLPG609 was terminated). While most studies suggest that FFAR2 suppresses human and mouse inflammation, further studies are needed to determine if and why FFAR2 promotes some types of inflammation.
the weakness of the C−Se bond and the easy oxidation of divalent selenium compounds. Per Paulmier, elemental selenium and diphenyl diselenide are sufficient selenium sources to produce most selenium intermediates at laboratory scale. Regulations generally exclude their use in pharmaceutical manufacture. Contrary to theoretical productions, selenium stablizes geminal carbanions slightly less than the corresponding sulfur compounds. Moreover, selenium is so nucleophilic that alkyl halides preferentially alkylate the selenium in many selenoether anions, before the halide collapses the resulting ylide in a nucleophilic substitution. Nevertheless, propargylic selenoether anions alkylate without deselenation, and then oxidize to α-selenoenones. Heated 1‑selena-2,3‑diazoles decompose to the corresponding alkyne.
20 March – The Tobacco and Vapes Bill, which would make it illegal for anyone born after 2009 to purchase cigarettes by raising the minimum age by a year starting in 2027, begins its process through Parliament. The Senedd approves Vaughan Gething as the next First Minister of Wales. 21 March – Carmen Smith is sworn in as the youngest member of the House of Lords. The Scottish Parliamentary Corporate Body confirms that members of Scottish Parliament staff will no longer be allowed to wear rainbow lanyards, or any other badge or jewellery associated with social issues, while at Holyrood. The Wildlife Management and Muirburn (Scotland) Bill passes its final vote in the Scottish Parliament. Among measures it introduces is a licensing scheme for land where grouse shooting takes place, and regulations for traps. Vaughan Gething announces his cabinet. Appointments include Jeremy Miles, who becomes Economy and Environment Minister and Lynne Neagle, who becomes Education Minister. Dan Barker, selected in December 2023 as the Conservative candidate for the 2024 Greater Manchester mayoral election, defects to Reform UK, accusing the Conservatives of giving up on the north of England. BBC News reports that officials have raised concerns about the role of secretary of state for the environment Steve Barclay in a proposed waste incinerator in his constituency, which he opposes, and he will consequently no longer have a role in the decision-making process.
Sources: en.wikipedia.org
No regulator in a major market has approved it for human use. It appears in research settings and in products marketed outside pharmacy channels. Legal status for personal possession varies by country.
Afamelanotide is a linear analog that has received approval in some jurisdictions for a specific photoprotection indication. Melanotan II is cyclic and less selective across melanocortin receptors. The two are related but are not interchangeable in regulatory or clinical terms.
A compound that activates several receptor subtypes may produce effects beyond pigmentation. Selectivity influences which tissues respond and shapes the side-effect profile described in reports. Designing subtype-selective analogs is a stated goal of melanocortin research.
Only a small number of early-stage human studies have been reported, and most were limited in size and duration. No large late-stage program has established a general efficacy or safety profile. The evidence base is therefore thin compared with approved medicines.