Melanotan II (MT-2)
Tanning through the melanocortin pathway — and a list of effects
Experimental material. Read before using anything from here.
Nothing on this page is a medical recommendation, prescription or treatment plan. It is an organized translation of protocols circulating in research communities and, where it exists, of what published trials tested. The two are marked differently — and they are not equivalent.
Most of the compounds here have no FDA approval for human use. Several are sold labeled "research use only", which means they have not gone through purity, sterility or dosage controls for human consumption. A community-reported dose is not a validated dose: it is what someone reported having done.
Talk to a licensed health professional before considering any of these compounds. If you already use one and feel anything unexpected, seek care — do not wait for the next routine test.
Summary
Synthetic peptide developed at the University of Arizona between the 1980s and 1990s. The goal was to induce tanning without prolonged sun exposure. It activates melanocortin receptors broadly, which brings along nausea, darkening of moles and an effect on erection.
Quick reference
- Route
- Subcutaneous is the most studied. The nasal spray has been tested, but is less predictable.
- Measure
- U-100 syringe. The calculation depends on how much bacteriostatic water goes into the 10 mg vial.
- Loading
- The common structure starts at 100–250 mcg/day and rises to 500–1,000 mcg as nausea allows.
- Maintenance
- After loading, it drops to 1–2 doses per week to hold the pigmentation.
Dose structure
| Stage | Days | Dose | Notes |
|---|---|---|---|
| Assessment | Days 1-3 | 100-250 mcg daily | Used to check how well nausea and flushing are tolerated. |
| Low loading | Days 4-14 | 250-500 mcg daily | Step up only if side effects stay manageable. |
| Standard loading | Weeks 3-6 | 500-1000 mcg daily | Continued until target pigment is reached. Brief UV exposure is often coordinated. |
Cycle Guidelines
| Approach | Duration | Off period | Best for |
|---|---|---|---|
| Short cycle | 4 weeks | 4+ weeks | First-time research planning |
| Standard cycle | 6 weeks | 4-6 weeks | Building visible pigment |
| Extended cycle | 8 weeks | 6+ weeks | Slower titration or stronger nausea profile |
Melanotan 2 Reconstitution Guide
| BAC Water Added | Concentration | 250 mcg | 500 mcg | 750 mcg | 1 mg |
|---|---|---|---|---|---|
| 1.0 mL | 10 mg/mL | 0.025 mL (2.5 u) | 0.05 mL (5 u) | 0.075 mL (7.5 u) | 0.10 mL (10 u) |
| 2.0 mL | 5 mg/mL | 0.05 mL (5 u) | 0.10 mL (10 u) | 0.15 mL (15 u) | 0.20 mL (20 u) |
| 3.0 mL | 3.33 mg/mL | 0.075 mL (7.5 u) | 0.15 mL (15 u) | 0.225 mL (22.5 u) | 0.30 mL (30 u) |
| 5.0 mL | 2 mg/mL | 0.125 mL (12.5 u) | 0.25 mL (25 u) | 0.375 mL (37.5 u) | 0.50 mL (50 u) |
Melanotan 2 Timeline & What to Monitor
| Window | Likely Pattern | What to Track |
|---|---|---|
| Days 1-3 | Most nausea and flushing happen here. Skin usually looks the same. | Tolerance level, whether bedtime dosing helps with nausea. |
| Weeks 1-2 | Some users notice freckling or slight darkening, especially with light UV exposure. | Mole photos, first signs of pigment change, side-effect intensity. |
| Weeks 3-4 | Pigment changes are more visible. Sexual and appetite effects often plateau. | Compare baseline mole photos. Note if any mole looks different. |
| Weeks 5-8 | Loading often wraps up here. Many users move to weekly maintenance. | Decide if the result is enough or if more loading is needed. |
| After loading | Pigment fades slowly without maintenance dosing or regular UV exposure. | How long pigment lasts at your chosen maintenance dose. |
Melanotan 2 vs PT-141 vs Afamelanotide
| Feature | Melanotan 2 | Afamelanotide (MT-I) | PT-141 (Bremelanotide) |
|---|---|---|---|
| Structure | Cyclic 7-amino acid peptide | Linear 13-amino acid peptide | Cyclic 7-amino acid derivative |
| Receptor focus | MC1R + MC3R + MC4R + MC5R (non-selective) | MC1R-preferring | MC3R/MC4R-preferring |
| Plasma half-life | ~1-2 hours | ~0.8-1.7 hours | ~2.7 hours |
| Main effect | Tanning + sexual + appetite changes | Tanning and photoprotection | Sexual arousal and desire |
| Tanning strength | Strong | Strong | Minimal |
| Sexual effect | Strong in ED studies | Not primary | Primary use case |
| Dose | Daily loading, then 1-2x weekly | Subcutaneous implant | On-demand, max 1 per 24 hours |
| FDA status | Not approved | Approved (Scenesse) for EPP | Approved (Vyleesi) for low female sexual desire |
| Nausea burden | High and dose-limiting | Lower in selective use | Common, listed on label |
Storage and handling
The rules below apply to practically every lyophilized peptide in this reference. Where a compound has its own requirement, it appears in the table in the previous section.
- Lyophilized powder, sealed: refrigerator, between 2 and 8 °C, protected from light. Many tolerate room temperature for short transport periods, but that is tolerance, not a recommendation.
- After reconstitution: always refrigerated, between 2 and 8 °C. The stability window drops to days or a few weeks, depending on the compound.
- Never freeze after reconstituting. The freeze–thaw cycle degrades the peptide.
- Do not shake. Swirl the vial slowly. Shaking breaks the peptide chain.
- Bacteriostatic water down the wall of the vial, in a slow stream, not squirted directly onto the powder.
- Cloudy solution, with particles or a color change: discard. There is no recovery.
Lab tests and monitoring
This list is the one that appears recurrently in the source, with small variations by compound. It serves as a starting point for a conversation with a professional — not as a substitute for that conversation.
- Before starting: complete blood count, comprehensive metabolic panel, lipid panel, fasting glucose and HbA1c, TSH and free T4, blood pressure and resting heart rate.
- Depending on the compound: IGF-1 (GH axis), lipase and amylase (VIP and the incretin agonists), serum copper and ceruloplasmin (GHK-Cu and blends containing it), CRP.
- Reassessment: most protocols review between week 4 and week 8, and then every 8–12 weeks.
- Do not wait for the routine lab test in the face of abdominal pain, visual changes, a change in a mole, shortness of breath, asymmetric swelling or any new and persistent symptom. That is a reason to seek care, not a spreadsheet item.
Evidence limits
Data source: peptidedosingprotocols.com, accessed on September 3, 2026. Translation and organization in Portuguese are original work. No primary source (PubMed, trial registry, package insert) was checked in building this page — the check was against the secondary source, and that alone.