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Melanotan II_Dosage, benefits & legal status

Also known as MT-2, MT-II, melanotan 2

Published July 22, 2026 · Updated July 25, 2026

A shot for a fast, deep tan, plus libido and appetite effects.

Tanning, libido, appetiteMelanocortin agonistResearch onlyHigh-risk
Common vial size10 mg
Dose0.25 up to 1 mg per dose (start low, increase slowly)
FrequencyDaily loading, then maintenance
RouteUnder the skin (subcutaneous)
StatusResearch only
CycledA loading phase, then maintenance, rather than a cycle

Common vial size is what vendors typically sell, not a recommendation. Enter your own vial in the calculator.

See how this dose compares across the library →

01

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.

The technical version

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.

02

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.

  1. 01
    MC1R produces the tan
    Faster and at lower doses than Melanotan I.
  2. 02
    MC4R produces the libido and appetite effects
    The same receptor PT-141 targets. PT-141 was developed from this molecule specifically to isolate that effect.
  3. 03
    Nausea, flushing and spontaneous erections follow from the same breadth
    These are not side effects in the usual sense, they are the drug hitting receptors it was never made selective for.
  4. 04
    Existing moles darken
    And there are case reports of new or changing melanocytic lesions. Anything that stimulates melanocytes systemically deserves caution here.
  5. 05
    It is not approved anywhere
    Unlike Melanotan I.
Anatomical illustration highlighting skin
WHERE THIS COMPOUND IS THOUGHT TO ACT:
Skin

03

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.
  • No dataIt 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

Research index

207

Papers and trials about Melanotan II

Searched: Melanotan II, Melanotan-II, melanotan 2.

Left out: MT-2 (too short to disambiguate without context).

49 papers tagged human · 35 not reviews or lab · 4 clinical trial publications

1 registered trials · none with posted results

Furthest stage reached: Phase 2, under way

Compare this against the whole library →

Nominated but withdrawn; previously category 2Regulators
In animals164
In the lab10
Reviews10
Senior author shareSpread across many groups

Evidence summary

Counted from Europe PMC indexing, not read by a person; a human tag can land on reviews, commentary or lab papers; clinical trial publications is the narrower count.

Melanotan II vial rendering
Compound field notes

At a glance

Four things to know about Melanotan II

01

Evidence

Research only

02

Category

Skin and cosmetic

03

Common vial

10 mg

04

Half-life

1 to 2 hours

04

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 cycle Community 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.

Compare this against the whole library →

05

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.

06

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.

Your vial size (mg)
Printed on the vial.
What you paid per vial
$
Used for cost per dose only.
Your dose (mg)
Commonly referenced range: 0.25 up to 1 mgCommunity practice

Choose your mix

your own mL
units · —
Enter your own volume

Measuring the water1 mL = one full 100-unit syringe.

YOUR DRAW5 / 100 units
What it costs

Melanotan II starts at $14.99 across 158 vendors, typically $2.50 – $5.00 per mg.

197 listings, last read Oct 24, 2026. Shipping and card fees are not included.

See all 197 listings →
07

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.

08

What are the side effects and cautions?

Known cautions and warnings for this compound.

Solubility, computed: 71% charged residues, 43% hydrophobic. Water usually sufficient.

A first-pass rule from peptide manufacturers' guidance. It does not account for disulfide bridges, salt form or how the powder was dried, and it predicts what should be easy rather than what will happen in your vial.

Who should avoid it

Check these before anything else.
  • 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

These are emergencies. Seek care.
  • 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

Expected, and usually mild.
  • 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

Where this page says nothing is established, that means nobody has studied it, not that a compound is safe.

09

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 labeled for laboratory research only, and there is no legal route to buy it for human use.

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 labeled 10 mg, so the dose you think you are taking may not be the dose you are taking.

What regulators say

From official documents

Guides for this compound

Sources

Beyond these, 207 records are indexed. Browse the records