Melanotan II_Dosage, benefits & legal status
Also known as MT-2, MT-II, melanotan 2
A shot for a fast, deep tan, plus libido and appetite effects.
Common vial size is what vendors typically sell, not a recommendation. Enter your own vial in the calculator.
What is Melanotan II?
Plain language first. The technical label stays, but it never stands alone.Overview
It tans skin fast and also boosts libido and cuts appetite, but hitting so many receptors is why it has more side effects. It is not approved.
Melanotan II is a broad melanocortin-receptor agonist, hitting several of the same receptors as the tanning and libido hormones.
What it's used for
A shot that gives a fast, deep tan, plus a libido boost and reduced appetite.
How does Melanotan II work?
What it does in the body, and where.Melanotan II hits several melanocortin receptors at once rather than just the pigment one. Every one of its extra effects, wanted and unwanted, comes from that lack of selectivity.
- 01MC1R produces the tanFaster and at lower doses than Melanotan I.
- 02MC4R produces the libido and appetite effectsThe same receptor PT-141 targets. PT-141 was developed from this molecule specifically to isolate that effect.
- 03Nausea, flushing and spontaneous erections follow from the same breadthThese are not side effects in the usual sense, they are the drug hitting receptors it was never made selective for.
- 04Existing moles darkenAnd there are case reports of new or changing melanocytic lesions. Anything that stimulates melanocytes systemically deserves caution here.
- 05It is not approved anywhereUnlike Melanotan I.
Where this compound is thought to act.
What else is it used for?
Each group carries its own evidence level.Approved means regulators have cleared it for that purpose. Investigational means it is in trials. Early research means it is being studied and is not established.
Tanning
Research only- Human trialIn an early human study, skin melanin rose in a dose-dependent way, with visible tanning after about five alternate-day doses.
- RegulatoryIt is not approved by the FDA or in Europe, and is linked to nausea, flushing, mole darkening, prolonged erections, and muscle breakdown.
Erections
Research only- Human trialIn a study of 20 men with erectile difficulty, 17 achieved erections without sexual stimulation.
- Human trialIn a placebo-controlled crossover of 10 men, 8 had clinically apparent erections.
- Human trialThis side effect is what led researchers to develop PT-141, which is now FDA-approved.
The published record
645
Records indexed for Melanotan II400 papers and 1 trials indexed in detail.
107 in humans, 79 of them original studies.
1 registered trials, 0 with posted results.
FDA: Named on the alert (Melanotan I and II) · FDA: Nominated but withdrawn; previously category 2.
Counted from Europe PMC indexing, not read by a person. Human means indexed under humans, which includes reviews and work on human cells. Original studies exclude reviews and lab work on human cells.Last updated 11 September 2026.
At a glance
Four things to know about Melanotan II
Evidence
Research only
Category
Weight loss and metabolic
Common vial
10 mg
Half-life
1 to 2 hours
How much, and do you cycle it?
The range, and whether you take breaks.0.25 up to 1 mg per dose (start low, increase slowly), daily loading, then maintenance. A loading phase, then maintenance, rather than a cycleCommunity practice
Frequent doses until the tan develops, then occasional top-ups to hold it. The structure comes from community practice and follows the pigment rather than any receptor recovery.
How long does it stay in the body?
The half-life, and where the figure comes from.1 to 2 hoursCommunity practice
Widely repeated. We have not traced it to a published human measurement.
Not yet traced to a primary source.
You can compare this against the whole library to see where it sits.
How do I dose and price it?
Enter your vial and your dose. Pick a mix. We show the draw and the cost.The vial holds a fixed amount of drug. Adding more water does not make more drug, it just spreads it thinner, so you draw a bigger number on the syringe for the same dose.
Choose your mix
Measuring the water1 mL = one full 100-unit syringe.
Your draw
5 / 100 unitsMelanotan II starts at $19.99 across 52 vendors, typically $2.80 – $5.00 per mg.
72 listings, last read Sep 5, 2026. Shipping and card fees are not included.
How do you store it?
Before mixing, and after.Dry powder in the freezer or fridge. Once mixed, fridge, and use within about a month.
Unmixed lyophilized Melanotan II keeps for a long time cold. Once you add water the clock starts: most reconstituted vials hold up for roughly 28 to 30 days at fridge temperature. Keep it out of light, and do not freeze it after mixing.
What are the side effects and cautions?
Known cautions and warnings for this compound.Who should avoid it
- Any history of skin cancer or melanoma
- Numerous, large, or atypical moles
- Pregnancy
- High blood pressure or heart problems, since it can raise blood pressure and heart rate
- It is not approved anywhere and is not permitted in pharmacy compounding, so nobody is screening you for any of the above
Stop and get help
- Any mole that changes in size, shape, or color, or starts to bleed or itch
- An erection lasting more than four hours, which has required surgery in reported cases
- Severe muscle pain with dark or cola-colored urine, which can signal muscle breakdown damaging the kidneys
- Severe headache with confusion, vision changes, or seizures
- A racing heart, sweating, and severe anxiety shortly after injecting
- Signs of an allergic reaction such as face or throat swelling, hives, or trouble breathing
Common effects
- Nausea, especially in the first few doses
- Facial flushing and yawning
- Darkening of skin, moles, and freckles, which is the intended effect but also the main concern
- New moles appearing, and existing ones becoming irregular
- Loss of appetite
- Spontaneous erections in men
What regulators say
- FDA: Import Alert 66-41: Detention Without Physical Examination of Unapproved New Drugs Promoted in the U.S., revised May 19, 2026Named on the alert (Melanotan I and II)
Products imported as non-human research, then sold on the internet as unapproved new drugs
Checked 11 September 2026 - FDA: Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks (category 2 and withdrawn nominations), current as of April 22, 2026Nominated but withdrawn; previously category 2
Published case reports of melanoma, posterior reversible encephalopathy syndrome, sympathomimetic toxidrome and priapism
Checked 11 September 2026
Where this page says nothing is established, that means nobody has studied it, not that a compound is safe.
Is Melanotan II approved?
And where the numbers on this page come from.No. Melanotan II is not approved for any use, anywhere. It is sold labelled for laboratory research only, and there is no legal route to buy it for human use.
- Approval statusResearch only
- RouteUnder the skin (subcutaneous)
- CheckedJuly 2026
What has happened recently
Not approved in any country and not permitted in pharmacy compounding. The UK regulator issued a public warning in 2009 and the FDA has sent warning letters to US distributors. Published case reports link it to melanoma, eruptive and atypical moles, ischemic priapism requiring surgery, muscle breakdown, kidney infarction, and a serious brain condition called posterior reversible encephalopathy syndrome. Whether it directly causes melanoma is unresolved, since users also tend to seek more sun, but the mole changes are consistently documented. Separately, testing of gray-market vials found actual peptide content ranging from about 4.3 to 8.8 mg in vials labelled 10 mg, so the dose you think you are taking may not be the dose you are taking.
You can compare this against the whole library, or read how to check a seller.
- DoseFrom research and community reports. No regulator has reviewed this dose.
- Vial sizeFrom what vendors typically list; not a recommendation.
- Sources
- Reviewed22 July 2026
What else is like Melanotan II?
Others in Fat loss without GLP-1, side by side.If you're weighing Melanotan II, it's worth reading Adipotide, BAM15, and Pancragen in the same class.
A shot for a fast, deep tan, plus libido and appetite effects.
- Dose
- 0.25 up to 1 mg per dose (start low, increase slowly)
- How often
- Daily loading, then maintenance
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- Research only
- How often
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- Dose
- Research only
- How often
- Daily, in 10-20 day courses
Guides for this compound
- How to Reconstitute a Peptide
Mix peptide powder with bacteriostatic water, step by step.
- How to Read an Insulin Syringe
Read the units, convert to millilitres, and draw the exact dose.
- mcg vs mg: The Peptide Dosing Mistake to Avoid
Your vial says mg and your protocol says mcg. Here is the conversion and how to check it.
- How to Read a Peptide COA
What the purity number does and does not tell you, and how to spot an edited report.
- How to Vet a Peptide Vendor
Independent COAs, HPLC purity, and the red flags that mean walk away.
Sources
- Case report and literature review, melanotan II and kidney infarction(2020)Reviews documented complications including priapism, muscle breakdown, kidney damage, and melanoma.
- Melanotan review, Actas Dermo-Sifiliograficas(2012)An opinion article by a Spanish dermatologist rather than a trial, and worth reading for the development history it records. Melanotan I and melanotan II were both built to increase melanin, and both work: injected, they raise eumelanin, the more protective pigment. Melanotan II was then dropped as a photoprotection candidate for a specific reason, that it also produced erections, because it binds melanocortin receptors far less selectively than melanotan I. That lack of selectivity is the whole story of this molecule. It is why the same compound is sold simultaneously for tanning, appetite suppression and libido, and it is why the side effects are not a separate list from the effects. The article also records what happened downstream: the nasal successor developed for erectile dysfunction, PT-141, worked in 80% of men who had not responded to sildenafil and was still never brought to market, because several patients developed high blood pressure. Reported harms in unlicensed users at the time were eruptive melanocytic naevi, changes in existing moles, and one melanoma case where causation could not be established. The author notes the drug is illegal in Spain, sold through gyms and websites, and that injection by untrained users carries its own infection risk. Treat this as informed clinical commentary, not evidence of efficacy or safety.
- FDA, bulk drug substances for compounding that may present significant safety risks(2026)The most specific adverse-event entry of any peptide on this page. FDA cites immunogenicity risk for certain routes from aggregation or peptide-related impurities, and then names published case reports of serious adverse events: melanoma, posterior reversible encephalopathy syndrome, sympathomimetic toxidrome and priapism. As of the 22 April 2026 version of this page, the substance sits in the second table, headed bulk drug substances nominated but withdrawn, rather than in the live category 2 list. The nomination was withdrawn, which is not the same as being approved or cleared: FDA still publishes the safety language above, and no longer has a nomination in front of it to evaluate.
Last reviewed 22 July 2026
Beyond these, 401 records are indexed. Browse the records