If you have been reading about Melanotan II and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2025-10-06. Numbers and descriptions here follow the published literature rather than marketing material.
Melanotan-2 is a synthetic linear peptide built from seven amino acids arranged in a short chain. Its sequence is commonly written as Ac-Nle-Asp-His-D-Phe-Arg-Trp-Lys-NH2, which includes a modified N-terminus and an amidated C-terminus. The molecule belongs to the melanocortin family and acts as a receptor agonist. Structural features such as the D-phenylalanine residue and the Nle substitution are associated with increased stability against enzymatic degradation relative to the natural parent peptide.
The compound emerged from research programs in the 1980s that examined analogues of alpha-melanocyte-stimulating hormone for pigmentation and photoprotection. Investigators modified the native sequence to extend activity duration and potency. A related analogue, afamelanotide, was developed within the same broad line of inquiry and eventually gained approval in certain jurisdictions for a rare light-sensitivity condition. Melanotan-2 itself did not progress through the same regulatory route and has no approved therapeutic indication.
Melanocortin receptors comprise five subtypes with distinct tissue distributions and functions. Melanotan-2 is described in the literature as a non-selective agonist that engages several of these subtypes, including MC1R, MC3R, MC4R, and MC5R. MC1R is the subtype most directly linked to melanin production in skin cells. Because the compound is not subtype-selective, its observed effects in experimental settings are generally attributed to activity across multiple receptor pathways rather than to a single target.
The compound was developed in the late 1980s and 1990s by academic researchers investigating photoprotection. The rationale held that stimulating melanin production might reduce ultraviolet damage to skin and lower skin cancer risk. Early work examined receptor binding, pigment response, and short-term tolerability in small studies. That program did not produce an approved drug, and formal development stalled after early-phase trials. Whether induced pigmentation confers meaningful photoprotection remains an open question.
Outside regulated medicine, melanotan II circulates through online vendors as a research chemical, often marketed for tanning. Products sold this way vary widely in purity, concentration, and labeling accuracy, and independent testing has documented discrepancies. Published reports describe both pigment effects and adverse reactions, including nausea, flushing, and darkening of existing moles. Long-term safety data are sparse, and no large controlled trial has established a risk profile. Questions about cumulative effects on melanocytes remain unresolved in the literature.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C50H69N15O9 | Free base; salt forms differ |
| Molecular weight | Approximately 1024 g/mol | Calculated for the free base |
| Appearance | White to off-white powder | Typically supplied as a lyophilised solid |
| Solubility | Soluble in water and polar solvents | Poorly soluble in non-polar solvents |
| Typical storage | -20 degrees Celsius, dry, protected from light | Refers to the solid form |
Research interest has centred on photoprotection and pigmentation, with a smaller body of work on appetite and sexual function. Published human data remain limited to small, frequently uncontrolled studies, and the compound has never received marketing approval from a national medicines regulator. Most laboratory work treats it as a pharmacological tool for probing melanocortin signalling in cell culture or animal models. Whether pigmentation changes observed in people translate into measurable protection against ultraviolet-induced DNA damage remains an open question.
Melanotan-2 is a synthetic cyclic heptapeptide designed as an analogue of alpha-melanocyte-stimulating hormone, the naturally occurring peptide involved in pigmentation signalling. Its sequence is conventionally written as Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2, with a lactam bridge joining the aspartate side chain to the lysine side chain. The empirical formula is C50H69N15O9 and the monoisotopic mass lies near 1023.5 daltons. N-terminal acetylation and the D-configured phenylalanine both increase resistance to enzymatic breakdown compared with the parent hormone.
Pharmacologically, melanotan-2 behaves as a non-selective agonist across the melanocortin receptor family. Binding at MC1R on dermal melanocytes promotes eumelanin synthesis, which underlies the tanning response described in early human work. Activity at the centrally expressed MC4R receptor is associated with reported effects on appetite and erectile function. Because the peptide does not discriminate strongly among receptor subtypes, attributing any single observed effect to one receptor pathway is generally not possible without selective antagonists or receptor knockout models.
Melanocytes are the pigment-producing cells of the skin, and they carry melanocortin-1 receptors on their surface. When the receptor is activated, cyclic adenosine monophosphate rises inside the cell and raises the activity of enzymes such as tyrosinase, which increases melanin output. Melanotan-2 binds melanocortin-1 receptors in vitro and in animal models, and this binding is generally described as the basis for the tanning effect. Other receptors account for different effects: melanocortin-4 receptors contribute to appetite and erectile signalling, while melanocortin-3 and melanocortin-5 receptors contribute to energy balance and exocrine function.
Early published reports described melanotan-2 as a tanning agent without sun protection, which means darkening is not the same as protection against ultraviolet radiation. Later studies explored the peptide in erectile dysfunction, hemorrhagic shock, and some skin conditions. No regulator in the United States or Europe has approved it for clinical use. Many products labelled melanotan-2 are sold without approval and their identity and purity are unverified. Its long-term safety in humans remains an open question.
No regulatory authority has approved melanotan-2 for human use, and several countries classify it as a prescription-only or controlled substance, which restricts lawful supply. Material sold online is generally labelled as a research chemical and is not required to meet pharmaceutical standards of identity or purity. Published human data consist mainly of small uncontrolled studies, case reports and adverse-event notifications, so the evidence base is descriptive rather than confirmatory. Whether repeated melanocyte stimulation alters long-term naevus behaviour remains an open question that no completed trial has resolved.
Melanotan-2 is a synthetic cyclic heptapeptide designed as a structural analogue of alpha-melanocyte-stimulating hormone, the endogenous tridecapeptide that regulates pigment production. Two modifications distinguish it from the natural hormone: norleucine replaces methionine at the N-terminus, which limits oxidation, and a D-phenylalanine substitution raises receptor affinity. The ring is closed through an aspartate-lysine lactam bridge, giving the molecule a constrained conformation. The free base has a molecular mass near 1024 daltons, and commercial material is usually supplied as an acetate salt. It appears in the literature as a research peptide rather than an approved therapeutic agent.
== Use == Functional beverages are commonly consumed by people seeking health benefits from their foods and beverages. Both convenience and health have been identified as important factors in consumers' decision-making about food and beverage purchases. Functional drinks are advertised as having various health benefits. For example, some claim to improve heart health, immunity, digestion, and joint health, while others promote themselves as satiating and energy-boosting.
Elsewhere, armed clashes between Taliban and Pakistan's border guards resumed along the border areas of Khost, Kunar, and Zabul provinces. According to Afghan local sources, clashes in Zabul province caused casualties among Taliban forces and destroyed several border outposts belonging to Taliban forces. In Torkham Border Crossing area, Pakistan officials state that they foiled an infiltration bid and killed an Afghan Taliban commander, identified as Qahraman, along with several of his associates. Pakistan claimed to have killed 67 Talban fighters as they attempted attempted assaults at 16 different locations in northern Balochistan, 27 were killed and several others wounded meanwhile a Frontier Corps soldier was killed and five were injured. 40 more Taliban fighters were killed in an attempted assault in KP. On 4 March, armed clashes between Taliban forces and Pakistani border guards continued in the border areas of Zabul, Kandahar, Khost, and Kunar provinces. An Afghan media outlet quoting local sources in several provinces report that many of the Pakistani strikes in recent days appeared to have targeted Taliban military facilities. They also reported that, over the previous week, the military corps of the Taliban-led Afghan armed forces in Nangarhar province had been struck by the PAF. On the same day, the PAF carried out multiple airstrikes in Kandahar targeting the Taliban-led Afghan armed forces' air brigade, the third battalion of the border police, and the 205 Al-Badr Corps.
Intraoperative stimulation has been employed a prognostic tool in people undergoing neurolysis surgery following nerve injury, where lower stimulation thresholds are associated with better postoperative motor recovery, whereas absent responses are associated with poor motor recovery, potentially warranting additional surgical interventions. Surgery can be done in case a nerve has become cut or otherwise divided, as well as when no recovery is achieved many months after injury. Recovery of a nerve after surgical repair depends mainly on the age of patients. Younger people fare better for prognosis due to the healing capacity of young tissues. Young children can recover almost normal nerve function. In contrast, a person over 60 years old with a cut nerve in the hand would expect to recover only protective sensory function, that is, the ability to distinguish hot/cold or sharp/dull; recovery of motor function would be likely incomplete. Many other factors also affect nerve recovery. An expanding area of nerve regeneration research deals with the development of scaffolding and bio-conduits. Scaffolding developed from bio-compatible material would be useful in nerve regeneration if they successfully exhibit essentially the same role as the endoneurial tubes, Schwann cells and epineurial fibroblasts do in guiding regrowing axons.
Following the earliest "Classical" style of the paintings at Kizil, which was especially elegant and "painterly", with sophisticated shading of the bodies to express sculptural volume, a new school appears with the Cave of the Statues, with works such as the "Cowherd Nanda", which is much bolder, using intense colors (but still limited to browns, greens and oranges), thicker lines and simpler patterns, somewhat like "colored drawings". This style is thought to be derived from the confluence of Hellenistic, Iranian and Indian influences under the Kushans, and its main center of creation was at Bamiyan, which became "a kind of parent monastery for the settlement of monks in Central Asia". This evolution in style is accompanied by a change in the main themes being portrayed. In the Classical period the story of the life of the Buddha and numerous Jataka tales took center stage. Now the main accent is on the sermons of the Buddha, which typically cover the walls of the main cella, together with the appearance of side and rear corridors in which are pictured the events of the death of the Buddha, the Parinirvana. Rhie attributes the sudden variations of styles at Kizil, without much signs of internal evolution (especially in the early stages), to the sudden arrival of new groups of artists from other regions, bringing their own artistic idioms and techniques.
Sources: en.wikipedia.org
A safety review reported that deaths from tyramine/MAOI-induced hypertension are extremely rare and that no deaths from MAOI-induced hypertension had been reported in the medical literature for several decades. Phenelzine should not be combined with drugs that have significant serotonin reuptake inhibition or significant serotonin-releasing activity, because of the risk of serotonin toxicity. Examples include selective serotonin reuptake inhibitors (SSRIs), serotonin–norepinephrine reuptake inhibitors (SNRIs), clomipramine, imipramine, MDMA, and certain analgesics such as meperidine, tramadol, methadone, tapentadol, dextromethorphan, dextropropoxyphene, pentazocine, and levorphanol. This serotonin-toxicity mechanism is distinct from the usual caution about overlapping MAO-inhibiting agents. Classic MAOI-to-classic MAOI overlap is not expected to cause serotonin toxicity by itself, although routine long-term coadministration is generally avoided because of limited safety data and lack of usual therapeutic rationale. Indirect monoamine-releasing sympathomimetics without significant serotonergic activity, such as ephedrine and pseudoephedrine, are not absolute contraindications, but may increase blood pressure and are generally avoided or used only cautiously at reduced doses with monitoring. Pseudoephedrine is considered less potent than ephedrine, and ephedrine less potent than amphetamine.
CF2ClCO2Na → NaCl + CF2 + CO2 Decarboxylations are an important in the malonic and acetoacetic ester synthesis. The Knoevenagel condensation and they allow keto acids serve as a stabilizing protecting group for carboxylic acid enols. For the free acids, conditions that deprotonate the carboxyl group (possibly protonating the electron-withdrawing group to form a zwitterionic tautomer) accelerate decarboxylation. A strong base is key to ketonization, in which a pair of carboxylic acids combine to the eponymous functional group:
However, the "absolute zero" on the Kelvin temperature scale was originally defined in terms of the second law of thermodynamics, which Thomson himself described in 1852. Thomson did not assume that this was equal to the "zero-volume point" of Charles's law, merely said that Charles's law provided the minimum temperature which could be attained. The two can be shown to be equivalent by Ludwig Boltzmann's statistical view of entropy (1870). However, Charles also stated:
=== Research === TRH has been evaluated for the treatment of various neurological disorders. It has been attempted for treatment of various epileptic disorders. TRH has been shown to improve outcomes of CNS injuries in experimental models. Efficacy for the treatment ALS and spinal muscle atrophy has not been demonstrated. Many individuals with depression exhibit a blunted endocrine response to TRH due to unknown reasons, and the response is correlated with clinical outcomes. Involvement of TRH in the pathogenesis of depression has nevertheless not been well established. TRH has undergone research for its ostensible antidepressant properties, however, results regarding efficacy have been inconsistent. One study on a small sample of people with treatment-resistant depression found short-lived anti-depressant and anti-suicidal effects when TRH was administered intrathecally. An orally bioavailable prodrug is being researched. In 2012, the U.S. Army awarded a research grant to develop a TRH nasal spray for suicide prevention amongst veterans. TRH acts as a wakefulness-promoting agent, causing awakening from sleep or sedation.
In May 2012, the ONDCP published "Principles of Modern Drug Policy", broadly focusing on public health, human rights, and criminal justice reform, while targeting drug traffickers. According to ONDCP director Kerlikowske, drug legalization is not the "silver bullet" solution to drug control, and success is not measured by the number of arrests made or prisons built. That month, a joint statement, "For a humane and balanced drug policy", was signed by Italy, Russia, Sweden, the United Kingdom and the US, promoting a combination of "enforcement to restrict the supply of drugs, with efforts to reduce demand and build recovery." Meanwhile, at the state level, 2012 saw Colorado and Washington become the first two states to legalize the recreational use of cannabis with the passage of Amendment 64 and Initiative 502 respectively. A 2013 ACLU report declared the anti-marijuana crusade a "war on people of color". The report found that "African Americans [were] 3.73 times more likely than whites to be apprehended despite nearly identical usage rates, and marijuana violations accounting for more than half of drug arrests nationwide during the previous decade". Under Obama's policies, nonwhite drug offenders received less excessive criminal sanctions, but by examining criminals as strictly violent or nonviolent, mass incarceration persisted.
Sources: en.wikipedia.org
No. Melanotan-2 is manufactured synthetically. The naturally occurring peptide in the same family is alpha-melanocyte-stimulating hormone, which the body produces as part of normal endocrine and neural signalling.
Both are synthetic analogues derived from the same parent hormone. Reference descriptions usually characterise afamelanotide as more selective for the MC1R subtype, whereas melanotan-2 is reported to interact with a wider range of melanocortin receptors.
Early studies explored melanocortin signalling and pigmentation, which later led to informal use of the label tanning peptide. That label is not a regulatory category and does not imply approved status for any purpose.
It is a synthetic cyclic peptide designed as an analog of alpha-melanocyte-stimulating hormone. It acts on melanocortin receptors and is best known from research into pigmentation. It is not an approved pharmaceutical product.