Melanotan II
MT-2MT-IIMelanotan 2Evidence
Preclinical
Half-life
1 h
Typical vial
10 mg
Route
Subcut
What it is
A melanocortin agonist that darkens skin by stimulating melanin production. Carries the most serious dermatological concern of anything on this site.
Melanotan II is a synthetic analogue of alpha-MSH, the hormone that signals pigment cells to produce melanin. Injecting it darkens skin over weeks, with far less sun exposure than would otherwise be needed. That is the effect people want and it does work.
It is not approved anywhere, and it is the compound on this site where regulators have been most vocal. Several national medicines agencies have issued public warnings about it by name. That is unusual.
The concern that matters is dermatological. Melanotan II stimulates melanocytes, the same cells melanoma arises from. Case reports describe existing moles darkening, changing shape, and in some instances melanoma being diagnosed in users. Causation in individual case reports is never settled, but the mechanism makes the association biologically plausible rather than coincidental, and that combination is why this page is written the way it is.
How it works
Melanotan II activates melanocortin receptors broadly. MC1R activity on melanocytes is what drives melanin production and the resulting tanning; MC4R activity in the brain accounts for the appetite suppression and sexual effects users also report.
Because it is non-selective, all of those effects arrive together. There is no dose at which it tans without also acting on the other receptors, which is the design difference between it and PT-141.
What it is studied for
Each entry states the evidence behind it. We do not rank indications by effectiveness — for most compounds here, that would be a claim nobody can support.
Skin pigmentation
Published reviewThe effect it is used for.
EvidenceWell documented that it produces tanning. No controlled trial establishes safety for this use.
Appetite suppression and sexual effects
Community practiceReported alongside the tanning.
EvidenceFollow from MC4R activity. Not studied as endpoints for this compound.
Regulatory status
Last reviewed 12 Aug 2026. Positions in this category change frequently, so we date the line.
Not approved for human use in any jurisdiction. Multiple national medicines regulators have issued public safety warnings specifically about melanotan products, citing unregulated manufacture and dermatological risk. Sold only as a research chemical.
Identity and clearance
What the molecule is, and how long a dose stays measurable.
Molecule
- Class
- Cyclic heptapeptide, non-selective melanocortin agonist
- Molecular weight
- 1024.2 Da
- Length
- 7 amino acids
Sequence
Ac-Nle-cyclo(Asp-His-D-Phe-Arg-Trp-Lys)-NH2
Structurally almost identical to PT-141. The difference in terminal group changes receptor selectivity substantially.
Pharmacokinetics
Published reviewShort-acting, but the pigmentation effect accumulates over weeks and persists for months after stopping.
Dose protocols reported in sources
Displayed for reference only. Every row says where it came from, and a trial protocol and a community convention are not the same kind of information. None of this is fed into the calculator, and none of it is a recommendation.
A week-by-week progression is also reported for Melanotan II. See it against a 10 mg vial, where the syringe units can be worked out.
| Goal | Dose | Frequency | Route | Units, 10 mg vial | Source | Start this protocol |
|---|---|---|---|---|---|---|
| Loading, commonly described | 250 mcg – 500 mcg | Daily until the desired pigmentation is reached | SubcutaneousCommunity sources describe starting low specifically because nausea is dose-related and pronounced. | 12.5–25 u | Community practice | Start this |
| Maintenance, commonly described | 500 mcg – 1 mg | One to two times weekly | Subcutaneous | 25–50 u | Community practice | Start this |
The doses above in syringe units, for the vial you have:
Start this copies a row into a protocol of your own, which you can then edit. Where a source gave a dose range or an ambiguous frequency, those fields arrive empty — we will not pick a number on your behalf.
CheckRows marked community practice describe what people commonly do, drawn from public discussion. They are not derived from any trial and are not evidence that a dose is safe or effective.
Work out what to draw
Pre-filled with a 10 mg vial as a worked example. These are not recommended values — change them to match the vial in front of you.
Draw to 5 units on a 1 mL U-100 syringe. That is 0.05 mL, containing 250 mcg of Melanotan II.
Check5 units falls between the printed lines on a 1 mL U-100 syringe. Mixing with 1.6 mL of water instead would put this dose at 4 units.
BioAlmanac performs arithmetic on values you enter. It does not recommend doses, schedules or compounds, and nothing here is medical advice. Confirm every calculation against your vial and syringe before drawing, and speak with a licensed healthcare provider.
Open this calculation in the full calculator
Units, concentration, bacteriostatic water — the glossary defines the vocabulary, and a unit is not a fixed volume.
Safety
Reported effects, the situations that need care, and the ones that mean stop.
Reported effects
- Nausea, sometimes severeCommunity practice
Very commonly reported
Dose-related and often pronounced in the first week.
- Facial flushingCommunity practice
Very commonly reported
- Darkening of existing moles and frecklesPublished review
Commonly reported
Expected from the mechanism, and the reason skin monitoring matters here more than anywhere else on this site.
- Spontaneous erectionsCommunity practice
Commonly reported in men
MC4R activity, the same mechanism PT-141 was developed around.
- New or changing pigmented lesions, including reported melanomaPublished review
Reported in case literature
Case reports describe melanoma diagnosed in users. Individual case reports cannot establish causation, but the mechanism makes the association plausible rather than coincidental.
When to stop
- Any mole that changes in size, shape, colour or border, or that bleeds or itches. Stop and see a dermatologist promptly. This is the specific risk this compound carries.
- Any new pigmented lesion.
- Severe or persistent nausea and vomiting.
- Any allergic response: rash, hives, facial swelling or difficulty breathing. Seek urgent care.
- An erection lasting more than four hours is a medical emergency — seek immediate care.
Interactions and situations that need care
- Melanoma history, atypical mole syndrome, or many molesAvoid
This compound stimulates the exact cell type melanoma arises from. Case reports describe melanoma diagnosed in users, and while individual reports cannot prove causation, deliberately stimulating melanocytes in someone already at elevated risk is the clearest avoidable hazard described anywhere on this site.
- Fair skin with heavy frecklingUse caution
The skin types most drawn to a tanning compound are the same ones at highest baseline melanoma risk, which makes dermatological monitoring more important rather than less.
- Pregnancy and breastfeedingAvoid
No reproductive or developmental safety data.
- Uncontrolled hypertension or cardiovascular diseaseUse caution
Melanocortin agonists raise blood pressure transiently, which is documented for the approved compound in this family.
What to expect
What the sources describe over time, and how confident anyone can be about it.
HonestlyThere is no human efficacy data for this compound, so there is no evidence-based timeline to give. Any site publishing a week-by-week schedule of expected effects has invented it.
- The tanning effect is real and develops over weeks, not days. It fades over months after stopping.
- Nausea in the first week is close to universal in community reports and is dose-related.
- It does not prevent sunburn. Darker skin is not protection from UV damage, and treating it as such is how people get burned while believing they are covered.
- Baseline photographs of your moles before starting, and a dermatologist who knows you are using it, are the two things that most reduce the risk this compound actually carries.
Storage and combinations
How to keep it, and what it does and does not go with.
Storage and handling
- Freeze-dried powder
- Refrigerated at 2–8 °C, protected from light.
- After mixing
- Refrigerated at 2–8 °C. Do not freeze once mixed.
- Long-term, frozen
- Unopened powder is stable at −20 °C or colder.
With other peptides
- PT-141caution
Both act on melanocortin receptors. Combining them stacks the same receptor family, compounding nausea, blood pressure effects and pigmentation changes.
- Afamelanotidecaution
Both drive pigmentation through the same receptor. Combining them stacks melanocyte stimulation for no additional effect, while adding melanotan II's nausea and blood pressure effects to a compound that avoids them.
Checking your vial
Research chemicals carry no manufacturing standard, so what the vial looks like is often the only quality signal available before you use it.
White cake, clear solution
Standard for a short cyclic peptide.
Collapsed cake, or any colour in the solution
Indicates degradation. A tanning peptide does not produce a coloured solution.
Vocabulary on this page
- Stack
- Several separate compounds run at the same time, each in its own vial and on its own schedule.
Questions
- Does Melanotan II protect against sunburn?
- No. It increases melanin, which is not the same as being protected from UV damage, and people using it routinely overestimate how much sun they can tolerate. It does not replace sunscreen.
- What is the melanoma concern exactly?
- The compound stimulates melanocytes, which are the cells melanoma arises from. Case reports describe moles darkening and changing in users, and melanoma being diagnosed. Case reports cannot establish causation, but the biological mechanism makes the association plausible. Which is why skin monitoring is the single most important thing on this page.
- How is it different from PT-141?
- They are structurally almost identical, differing in one terminal group. That one difference changes receptor selectivity substantially. PT-141 has weak pigmentation activity and holds an FDA approval; melanotan II is non-selective, tans strongly, and is approved nowhere.
References
Everything on this page that came from a source, with the source.
Melanotan-associated melanoma and pigmented lesion change: a review of reported cases
Dermatology review literature, 2019 · Review of case reports
Humans
Collects reports of pigmented lesion change and melanoma diagnosis in melanotan users, and notes that causation cannot be established from case reports while the melanocyte-stimulating mechanism provides biological plausibility.
Commonly reported community protocols
BioAlmanac editorial summary of public community sources, 2026 · Not a study
Summarises loading and maintenance dose patterns described in public discussion. Carries no evidential weight about safety or effect.
Compiled community protocols
BioAlmanac editorial summary of a public protocol compilation, 2026 · Not a study
Records a week-by-week progression described on a vendor-adjacent protocol site, retrieved August 2026. Only the doses are taken from it. Its own syringe-unit conversions were checked against the vial sizes it states and several understate the volume by half, so nothing computed by that source is reproduced here — the units on this site are worked out from the vial in front of you. Carries no evidential weight about safety or effect.
Melanotan II compared with
Also compared with GHK-Cu, AHK-Cu, SNAP-8, Afamelanotide, Glutathione, GLOW.
Related compounds
PT-141
A melanocortin receptor agonist approved by the FDA for low sexual desire in premenopausal women. It acts on the brain rather than on blood flow.
Afamelanotide
The approved member of the melanotan family. Same idea as melanotan II, taken through a full regulatory process, and the contrast between them is instructive.
GHK-Cu
A naturally occurring copper-binding tripeptide with a long history in topical skincare research. Injected use is not what the research studied.
AHK-Cu
GHK-Cu's less-studied sibling, used topically for hair. Almost all the research people cite for it is actually GHK-Cu research.
Next
What to do with Melanotan II
- Keep a record of itTurn a dose and a schedule into a protocol, then log what you actually take. Melanotan II is filled in for you.
- See what it costsPer-milligram prices read from vendor sites and confirmed by a person, so vial sizes compare.
- Check a combinationWhat our profiles record about Melanotan II alongside each other compound — including the pairs where nothing is recorded.
Keep this page honest
If something here is wrong, out of date, or missing a source, tell us and we will fix it and say that we did.
This page is educational. It describes what published research reports, not what you should do. Peptides discussed here are largely not approved for human use, and nothing on BioAlmanac is medical advice. No clinician reviews these pages.
Page last updated 12 Aug 2026