TL;DR: Melanotan 2 dosing in the research literature is split into two phases — a loading phase to build pigment, then a lower maintenance phase to hold it. Doses are small (micrograms), UV exposure is still required for the tan to develop, and starting at a low dose is the single most-cited way to manage the early nausea. This guide covers the phase logic and the concentration maths.
Melanotan 2 — widely nicknamed the “Barbie peptide” or “tan jab” in 2026 coverage — is dosed differently from most research peptides because its effect (pigmentation) accumulates and is then maintained. Understanding the loading-vs-maintenance structure is the key to reading any Melanotan 2 protocol. For how it differs from its more selective sibling, see Melanotan 1 vs Melanotan 2.
The Two-Phase Structure
Because Melanotan 2 builds and then holds pigment, protocols separate two phases:
- 1
Loading phase
Higher frequency to build pigment up to the desired level.
- 2
Maintenance phase
A lower, less frequent dose to hold the pigment once reached.
- 3
UV still needed
Melanotan 2 primes melanocytes; UV exposure is what actually develops the tan.
A critical and frequently-missed point: Melanotan 2 does not tan you on its own. It sensitises the melanocytes, but UV exposure is still what triggers pigment production. The peptide reduces the UV dose needed, it does not replace it.
Research Dosing Ranges
The figures below reflect general ranges reported in the research literature and are provided for educational context only. They are not medical instructions and are not intended for human use.
| Phase | Dose | Frequency |
|---|---|---|
| Loading (low start) | 100-250mcg | Building up |
| Loading (typical) | 250-500mcg | Building up |
| Maintenance | 500-1000mcg | 1-2x weekly |
Qualitative from the research literature; not a recommendation.
Start low. The most consistent handling note in the literature is that the early nausea and facial flushing are dose-dependent, so beginning at the low end (around 100mcg) and increasing gradually is how tolerance is built. Jumping straight to a high dose is what produces the worst early nausea.
Reconstitution & Concentration Maths
Melanotan 2 is dosed in micrograms from a milligram vial, so the reconstitution volume sets how precise each tiny draw is. A worked example for a 10mg vial:
| Peptide | BAC Water | Concentration | 500mcg dose = |
|---|---|---|---|
| 10mg | 2mL | 5mg/mL | 0.10mL (10 units) |
| 10mg | 1mL | 10mg/mL | 0.05mL (5 units) |
A larger reconstitution volume makes each microgram dose easier to measure accurately. Model your Melanotan 2 (10mg) vial in the reconstitution calculator, and see the peptide reconstitution guide for procedure.
Side Effects to Account For
Melanotan 2’s broader melanocortin receptor activity means a broader side-effect list than the more selective Melanotan 1:
- Nausea and flushing — early, dose-dependent, ease with a low start
- Appetite suppression — from MC4R activity
- Spontaneous erections — from MC3/4R activity
- Darkening of moles and freckles — shared with all melanotan compounds; our melanotan, moles and freckles guide covers monitoring
For the underlying mechanism, see what is Melanotan 2.
Storage & Stability
- Lyophilised powder: store at -20°C for long-term stability
- Reconstituted solution: store at 2-8°C (refrigerated), protected from light
- Avoid repeated freeze-thaw cycles
See the peptide storage guide for general principles.
Safety, Legality & Research Disclaimers
Melanotan 2 is a research peptide. It is not an approved medicine and has not been authorised for therapeutic use anywhere. It should be treated strictly as a laboratory research chemical, handled by qualified individuals, and used only for legitimate research purposes — not as a cosmetic tanning product. Regulatory status varies by jurisdiction, and researchers are responsible for confirming compliance with applicable local laws and institutional requirements. Nothing here is medical advice.
FAQ
What is the loading phase for Melanotan 2?
The loading phase uses more frequent microgram doses to build pigment up to the desired level. Once reached, protocols switch to a lower, less frequent maintenance dose (often 1-2x weekly) to hold the tan. The two-phase structure exists because Melanotan 2’s effect accumulates and is then maintained.
Does Melanotan 2 work without sun or UV?
No. Melanotan 2 sensitises the melanocytes but does not produce pigment on its own — UV exposure is still required to develop the tan. The peptide reduces the amount of UV needed; it does not replace it.
How do I reduce Melanotan 2 nausea?
Start at a low dose (around 100mcg) and increase gradually. The nausea and facial flushing are dose-dependent, so a low starting dose is the most-cited way to build tolerance. Jumping to a high dose produces the worst early nausea.
How much bacteriostatic water for a 10mg Melanotan 2 vial?
For a 10mg vial, 2mL of bacteriostatic water gives 5mg/mL, so a 500mcg research dose is 0.10mL (10 units on a U-100 syringe). A larger volume makes small microgram doses easier to measure. Use the reconstitution calculator to model other combinations.
References
- Research literature on Melanotan II melanocortin receptor pharmacology and UV-dependent melanogenesis.
- Research literature on Melanotan II dose-dependent nausea, flushing, and appetite effects.
Last updated: July 17, 2026
Disclaimer: This information is for educational and research purposes only. Peptides are research chemicals not intended for human consumption. Model your vial in the reconstitution calculator.