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Melanotan 2 Dosage Calculator and Chart: Loading Dose by Skin Type
Melanotan 2 dosage for the 10mg vial: units with 2mL of bac water, loading and maintenance, timing, the sun question and how long a mixed vial keeps.
Melanotan 2 is a tanning peptide measured in micrograms, and a 10mg vial goes a long way: at the 500mcg draw most protocols settle on, it holds 20 of them. Melanotan II, or MT2, is a ring of seven amino acids modelled on alpha-MSH, the body’s own signal for melanin production. Chemists at the University of Arizona built it in the late 1980s, and it reaches more of the body’s melanocortin receptors than the pigment one, which is why appetite, nausea and libido come up in the same breath as the tan.
Simms Research’s Melanotan II comes as a 10mg vial at $55. Everything below is for that vial on its own; whether Melanotan 1 suits a project better is the question Melanotan 1 vs 2 answers.
Melanotan 2 dosage calculator
Pick the water and the dose, and the calculator gives the units to draw on a U-100 insulin syringe. It opens on a 10mg vial with 2mL and a 500mcg dose: 10 units.
Melanotan 2 dosage chart
500mcg is the working draw, reached after a few evenings at 100 to 250mcg, and it runs in two phases: daily loading until the colour is there, then occasional maintenance draws to hold it. Mixed with 2mL, the 10mg vial puts 50mcg behind each line of a U-100 insulin syringe, so every amount lands on a whole unit:
| Phase | Amount | Syringe units (U-100) | How often |
|---|---|---|---|
| First 2 to 3 days | 100 to 250mcg | 2 to 5 units | Once a day, evening |
| Loading | 500mcg | 10 units | Once a day, evening |
| Maintenance | 500mcg | 10 units | Once or twice weekly |
| Maintenance, single draw | 1mg | 20 units | Once a week |
Nobody scales these draws to body size. The trials that first gave MT2 to people did, opening at the equivalent of about 700mcg for a 70kg adult and settling on about 1.75mg (Dorr, Life Sciences, 1996). Today’s range sits beneath that opening dose, because nausea rises with the size of the draw. Any other vial size or water volume goes through the peptide calculator.
Melanotan 2 reconstitution
2mL of bac water goes into the 10mg vial. That works out to 50mcg a unit: 2 units is 100mcg, 5 units is 250mcg, 10 units is 500mcg and 20 units is 1mg, which covers every draw in the chart without a calculation.
The water goes in slowly against the side of the vial, and a gentle swirl, never a shake, finishes the job. MT2 dissolves fast, inside a couple of minutes, to a solution as colourless as the water was. Mark the mixing date on it and store it cold and dark. The full routine for any vial is in how to reconstitute peptides.
A 10mL vial of Research Water ($20), Simms Research’s bac water with 0.9% benzyl alcohol, mixes five Melanotan II vials. The bac water guide explains why it suits a vial opened again and again over weeks.
Melanotan 2 loading dose and maintenance dose
Loading is 500mcg, 10 units, once a day; maintenance is the same 500mcg once or twice a week. Before loading, protocols spend two or three evenings at 100 to 250mcg, because the first draws bring the most nausea and the body settles into it within days.
Loading is the phase that builds pigment. It runs until the shade is where the project wants it, most often one to three weeks, and longer on very fair skin. Maintenance then holds the colour against the skin’s own turnover, which replaces the outer layer every few weeks and takes the melanin with it. Some protocols fold the week’s maintenance into a single 1mg draw of 20 units; the result is the same, with more of the side effects arriving on that one evening.
A slower route stays at 100 to 250mcg daily throughout, the low or micro dose protocol, trading speed for a gentler first fortnight. Long runs are broken up: eight to twelve weeks of use, then a few weeks off before loading again, which is quicker the second time because some colour remains.
Melanotan 2 dosage by skin type
Skin type changes how long loading runs and how often maintenance comes round, not the size of the draw. The MT2 trials didn’t split their results by skin type; the protocols in circulation do, along the six Fitzpatrick types that sort skin by how it reacts to summer sun:
| Skin type | First draws | Loading at 500mcg a day | Maintenance at 500mcg |
|---|---|---|---|
| I to II: very fair, burns easily | 100mcg (2 units) | 3 to 4 weeks or more | Twice a week |
| III: medium, tans gradually | 250mcg (5 units) | 2 to 3 weeks | Once or twice a week |
| IV to V: olive to brown, tans easily | 250mcg (5 units) | 1 to 2 weeks | Once a week or less |
Very fair skin and red hair usually come with variants of the pigment receptor MC1R that answer the hormone signal weakly. Their pigment cells lean towards the red-yellow pheomelanin and switch to brown eumelanin slowly, so those protocols open lowest, load longest and end with a lighter shade. Olive and brown skin already makes plenty of eumelanin and deepens within days.
When to take Melanotan 2: morning or night
Night. The nausea, the warm flush across the face and the yawning that follow a draw all come within the first hours, and an evening draw lets most of that pass during sleep. In the 1996 trial the other effect men noticed, spontaneous erections, ran for one to five hours after each injection, which also points to the evening.
Protocols also keep the draw away from a large meal, since nausea is heavier on a full stomach, and keep the same time each day through loading. The time of day changes how the evening feels, not how quickly the tan develops.
Does Melanotan 2 work without sun?
Yes, more slowly and to a lighter shade. In the first human trial, the colour that two of the three men developed showed on the buttocks as well as the face and upper body, skin that usually stays covered, and it was measured a week after their last injection. MT2 pushes pigment cells to make more eumelanin on its own.
Sunlight is what darkens that new melanin and lifts it towards the surface, the part of a tan UV does within hours. So protocols add brief sun or sunbed sessions during loading, 10 to 15 minutes, kept well short of a burn. Without them, in winter or with the sun kept off, the same draws build colour over more weeks and settle a shade lighter.
Melanotan 2 before and after: how long it takes
A visible tan takes one to two weeks on medium skin and three to six on very fair skin, counted from the first loading draw. The first change is in freckles and moles, which darken within the opening week, before the even colour reaches the face, shoulders and arms.
Most before-and-after pictures are taken around week three or four, when loading has finished and the shade is set. The colour then holds for as long as maintenance continues. Once the draws stop it fades over one to two months as the outer skin renews, the same way a summer tan leaves, and restarting later needs a shorter load.
How long Melanotan 2 lasts once reconstituted
28 days, kept at fridge temperature, 2 to 8°C, and out of the light. Unopened powder is far hardier: weeks at room temperature do it no harm, so Simms Research sends it without cold packs, and a freezer at −20°C holds it longest. Powder and mixed vial are laid out side by side in the peptide refrigeration guide.
The 28 days decide how far a 10mg vial goes. Loading draws it fast: three weeks, opening evenings included, use nearly the whole vial inside its window. Maintenance draws it slowly, and the window closes first, as two 500mcg draws a week take 4mg in four weeks. Each month of maintenance therefore opens a fresh vial, and a run of three weeks’ loading and two months’ maintenance takes three.
Melanotan 2 nasal spray vs injection
The dosing charts, this one included, are written for injection. A nasal spray comes premixed at its maker’s own strength, so a spray has no unit count, and the lining of the nose absorbs a smaller and less even share of each one. No published study has measured how much MT2 gets through it.
MT2’s closest relative shows why that matters. Bremelanotide (PT-141) began as a nasal spray, and its developer moved it to an injection after uneven uptake through the nose left some people with far higher blood levels than others. Protocols that do use sprays run two to three times the injected amount to cover the loss.
Melanotan 2 side effects
Most of what MT2 does besides tanning shows up in the first few draws and eases as loading goes on: nausea, a warm flush across the face, yawning and stretching, and a smaller appetite. In the University of Arizona trials the nausea was mild at most dose levels and passed without treatment. At the dose the later trials used, about 1.75mg for a 70kg man and three and a half times today’s usual draw, 12.9% of subjects had severe nausea (Wessells, International Journal of Impotence Research, 2000).
Men in those trials also had spontaneous erections for one to five hours after a dose. That comes through MC4R, the receptor behind the appetite effect too, and it is the line of research PT-141 grew out of.
Freckles and moles darken along with the rest of the skin, often before it, and that is the effect dermatologists have written about. Case reports since 2009 describe moles darkening quickly and new ones appearing during use (Langan, BMJ, 2009; Cousen, British Journal of Dermatology, 2009).
Melanotan II lab results
Every vial tested held more than 10mg. Simms Research has published two Melanotan II batches, and the newer one, tested on July 16, 2026, was split across three vials:
| Sample | Net content | Purity (RP-HPLC) |
|---|---|---|
| First vial | 10.12mg | 99.68% |
| Second vial | 11.43mg | 99.51% |
| Third vial | 10.92mg | 99.84% |
| Batch average | 10.82mg | 99.68% |
LC-MS confirmed the compound. The panel also covered endotoxins (pass), heavy metals (none found among arsenic, lead, cadmium and mercury) and sterility (no growth). April 2026’s batch, the earlier of the two, came in at 10.43mg and 99.29% on one vial with an endotoxin pass; heavy metals and sterility weren’t yet part of the testing.
That surplus nudges every draw up slightly: spread through 2mL, 10.82mg makes a 10-unit draw closer to 541mcg than 500. The calculator takes the certificate’s number in place of 10mg for exact units. The Melanotan II lab results page has both certificates in full, and how to read a peptide COA walks through each field.
Frequently asked questions
How many units of Melanotan 2?
10 units for 500mcg with 2mL in the 10mg vial; 5 units is 250mcg and 2 units is 100mcg. Units follow the water, so a chart written for 1mL puts 500mcg at 5 units and one written for 3mL at 15.
Is Melanotan 2 the same as PT-141?
No. PT-141, or bremelanotide, is MT2 with the amide at the end of its chain replaced by an acid. It was developed for sexual desire rather than tanning and approved in 2019 as Vyleesi. It has its own 10mg vial at Simms Research: PT-141.
Does Melanotan 2 work on redheads?
Yes, slowly. Red hair usually comes with MC1R variants that respond weakly, so protocols open at 100mcg, load for four weeks or more and expect a lighter result than on olive skin.
Do Melanotan 2 freckles go away?
The darkening fades back with the tan once the draws stop, as the skin renews over the following months.
Does Melanotan 2 help with weight loss?
MC4R lowers appetite during loading, yet no study has tested MT2 for weight loss, and protocols don’t dose it for that.
Is Melanotan 2 safe?
In the small university trials it was tolerated at doses well above today’s, with side effects that passed within hours. It never went through approval, so there is no long-term record, and Simms Research supplies it for laboratory research only.
Should I choose Melanotan 1 or 2?
Melanotan 1 acts mainly on the pigment receptor and tans more slowly, with fewer of the effects above. The two are set side by side in Melanotan 1 vs 2.