Melanotan II
Synthetic Melanocortin Peptide | Tanning & Sexual Function
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What is Melanotan II?
Melanotan II is a lab-made peptide modeled on a natural hormone called alpha-MSH, which activates melanocortin receptors involved in skin pigmentation and several other body systems. It was originally developed at a university research lab to study sunless-tanning pathways, and later research also looked at its effects on melanocortin receptors tied to appetite and arousal pathways in small clinical studies. Melanotan II has never been approved for human use by the FDA or Health Canada, and it's sold here strictly as a research chemical for laboratory study, not for use in people.
Key terms:
Melanotan II is a synthetic melanocortin receptor agonist.
Melanotan II is a lab-made version of alpha-melanocyte-stimulating hormone (α-MSH), a natural hormone. It prompts cells to make melanin, the pigment behind skin tanning. Research reports separate effects on sexual arousal and on reduced appetite. It was first developed at the University of Arizona as a sunless tanning agent. Attention since then has focused on its two-sided profile — pigmentation and sexual function — both driven by melanocortin receptor activation.
Key research areas
- Rapid tanning without UV exposure
- Enhanced libido and sexual function
- Appetite suppression
- Improved mood through melanocortin activation
- Photoprotection via increased melanin
Researched dosing
This table reflects the study designs and dose ranges researchers have used with Melanotan II in the cited literature — research methodology reference, not usage instructions.
| Phase | Dose | Frequency | Route |
|---|---|---|---|
| Loading protocol | 0.25mg | Daily | Subcutaneous |
| Pigmentation maintenance studies | 0.5-1mg | 2-3x weekly | Subcutaneous |
| Sexual-function studies | 0.5-1mg | As needed | Subcutaneous |
| Lower-dose tolerability studies | 0.1-0.25mg | Every other day | Subcutaneous |
| Photoprotection studies | 0.5mg | 2x weekly | Subcutaneous |
Commonly cycled 8 weeks on, 4+ weeks off.
How it works
At the cell level, Melanotan II research looks at how the peptide activates melanocortin receptors distributed across the body (skin, brain, and elsewhere) — the receptor names below (MC1R, MC4R) are just labels for which cell types respond.
Binds to melanocortin receptors (MC1R, MC3R, MC4R, MC5R) throughout the body. MC1R activation stimulates melanocytes to produce eumelanin, while MC4R affects sexual arousal and appetite regulation.
Pharmacokinetics
This chart shows how a research dose of Melanotan II is absorbed and cleared over time in the cited studies — read it like a timer: the peak is when levels are highest, then the curve trails off as the compound clears.
- Peak
- 0.5 hr
- Half-life
- 1 hrs
- Cleared
- ~5 hrs
Dorr et al. 1996
Research applications
This section summarizes the research areas — melanocortin-receptor pathways in skin, hormonal, and metabolic systems — that scientists have studied for Melanotan II; it's a summary of published research, not medical claims about outcomes for a person, and Melanotan II is not approved for human use.
Skin Health
Stimulates natural melanin production for darker skin tone without sun damage. Increased melanin provides natural SPF and reduces sunburn risk. Promotes uniform tanning and may help with certain pigmentation disorders.
Hormonal
MC4R activation leads to enhanced libido and sexual function. Female sexual arousal disorder trial showed 73% of premenopausal women reported arousal in a crossover study with 0.025mg/kg single dose.
Metabolic
MC3R and MC4R activation contributes to appetite suppression and potential metabolic effects.
Dosage reference
- Doses used in research
- 0.25–1 mg
- Frequency in studies
- Daily initially, then 2-3x weekly for maintenance
- Handling
- Reconstituted solution — research use only; not for administration
- Timeline reported in studies
- Tanning: 7-10 days, Sexual: 2-4 hours, Appetite: immediate
- Storage
- Refrigerate reconstituted peptide, protect from light
- Cycle length
- Literature references 4-8 week study windows separated by ~4-week intervals
- Break between cycles
- 4 weeks minimum to assess melanin fading
Interactions
This list shows which other compounds researchers have studied alongside Melanotan II, and flags pairings that call for extra caution in a research setting.
Reconstitution & storage
This is the standard laboratory method for turning freeze-dried Melanotan II powder into a liquid research solution — note that the solution is light-sensitive, a chemistry-handling detail, not a usage instruction.
- Allow vial to reach room temperature (15-20 minutes)
- Clean vial top with alcohol swab and allow to dry
- Calculate required bacteriostatic water volume using the calculator below
- Draw calculated volume of bacteriostatic water into syringe
- Inject water slowly down the inside wall of the vial (never directly onto powder)
- Gently swirl until powder completely dissolves (never shake)
- Solution should be clear to slightly yellow - discard if cloudy or contains particles
- Wrap vial in foil - solution is light-sensitive
- Store the reconstituted solution refrigerated (2–8°C), labeled with the date and concentration, for laboratory research use only.
Lyophilized: Room temperature (dark location), use within Per manufacturer expiration
Reconstituted: 2-6°C, use within 30 days
Open the Melanotan II reconstitution calculatorQuality indicators
These are the visual and lab-report checks researchers use to confirm a Melanotan II sample is pure and correctly identified before it goes into a study — a quick sanity check against the Certificate of Analysis (COA), not a guarantee.
White to off-white lyophilized powder - Pure MT-II appears as white or slightly off-white powder before reconstitution
Clear to pale yellow when reconstituted - Properly mixed solution should be transparent with at most a slight yellow tint
Protect from light exposure - MT-II is photosensitive - wrap vial in foil and minimize light exposure
Brown or dark colored powder - Indicates oxidation or impurities - do not use
Cloudy solution after mixing - Suggests degradation or contamination - discard immediately
Vacuum sealed vial - Quality MT-II comes vacuum sealed - you should hear a "pop" when penetrating stopper
What to expect
This timeline summarizes what the cited research literature reports at each study stage — research context for comparing studies, not a personal-results promise, and not medical guidance.
Possible nausea, flushing, and fatigue after injection
Increased spontaneous erections (men), enhanced arousal
Noticeable skin darkening, reduced appetite
Significant tanning, stabilized sexual effects
Maintained tan with less frequent dosing
Safety notes
This section covers handling cautions and regulatory notes for Melanotan II — it is not FDA-approved for human use, and this is research-use-only scope, not medical advice.
- Start with very low dose (0.1-0.25mg) to assess tolerance
- Avoid if history of melanoma or dysplastic nevi
- Monitor moles and freckles for changes in size or color
- Stay hydrated to minimize headaches and flushing
- Blood pressure may increase temporarily after injection
- Not FDA-approved for human use - research peptide only
Regulatory status
- Not approved by the FDA for any indication.
- Supplied and described for laboratory research use only — not for human or veterinary use.
Community data
Community Insights
Based on data the community reported. Not clinical proof.
Frequently asked questions
What is Melanotan II?
Melanotan II is a synthetic analog of alpha-melanocyte-stimulating hormone (α-MSH), a naturally occurring hormone. It was originally developed at the University of Arizona to study melanocortin-receptor pathways. Melanotan II has never been approved for human use by the FDA or Health Canada, and Lux BioPure supplies it strictly as a research chemical for laboratory study, not for use in people.
What class of compound is Melanotan II?
Melanotan II is classified as a synthetic melanocortin-receptor agonist. In laboratory research it is described as binding melanocortin receptors — MC1R, MC3R, MC4R, and MC5R — that are distributed across different cell types in the body. These receptor labels simply identify which cells respond in a study; the compound is handled purely as a research material with no human-use application.
How is Melanotan II typically reconstituted for research use?
In laboratory settings, the vial is brought to room temperature and the stopper cleaned with an alcohol swab, then bacteriostatic water is added slowly down the vial wall — not onto the powder — and gently swirled until dissolved. A correct solution is clear to slightly yellow. Because the compound is light-sensitive, the vial is wrapped in foil and refrigerated.
How do researchers verify a Melanotan II sample?
Researchers check that lyophilized Melanotan II appears as a white to off-white powder and that, once reconstituted, the solution is clear to pale yellow with no cloudiness or particles. Brown or dark powder suggests oxidation, and a cloudy solution suggests degradation or contamination — both are reasons to discard. These are visual checks against the Certificate of Analysis, not a guarantee.
Is Melanotan II legal to purchase for research in Canada?
Lux BioPure sells Melanotan II in Canada strictly as a research-use-only chemical for laboratory study — it is not for human or veterinary use and is not offered as a drug or supplement. Melanotan II has never been approved for human use by the FDA or Health Canada; it is supplied only as a research peptide.
References
Comprehensive cardiovascular monitoring revealed transient increases in blood pressure and heart rate, typically mild and self-limiting but requiring consideration in at-risk populations.
Long-term study showed sustained increase in melanin production and significant reduction in UV-induced erythema in individuals with high sunburn susceptibility (Fitzpatrick Type I-II).
Crossover study in premenopausal women with sexual arousal disorder showed significant increases in genital arousal and sexual desire within 24 hours of administration. 73% reported arousal.