What Are Melanotan I and Melanotan II?
Melanotan I (afamelanotide) and Melanotan II are synthetic analogs of alpha-melanocyte-stimulating hormone (alpha-MSH), a natural peptide that regulates melanin production. While they share a common origin, they are very different molecules with distinct risk profiles.
MT-1 vs. MT-2 at a Glance
| Property | Melanotan I (MT-1) | Melanotan II (MT-2) |
|---|---|---|
| Other Names | Afamelanotide | N/A |
| Structure | Linear peptide | Cyclic peptide |
| Molecular Weight | ~1,647 Da | ~1,024 Da |
| Receptor Selectivity | MC1R (selective) | MC1R, MC3R, MC4R, MC5R (broad) |
| FDA Approved | Yes (Scenesse, for EPP only) | No |
| Gray Market Availability | Rare | Very common |
| Category 1 Expected | No | No |
Research Areas of Interest
- Skin pigmentation/tanning — both MT-1 and MT-2 stimulate melanin production
- Photoprotection — MT-1 specifically studied for UV damage protection in patients with EPP
- Sexual function — MT-2's MC4R activity led to development of bremelanotide (Vyleesi), an FDA-approved drug for female sexual dysfunction
Important Safety Considerations
Melanotan peptides carry more safety concerns than many other popular peptides. Buyers should carefully understand the risk profile before sourcing.
- Mole changes — melanin stimulation can darken existing moles and make skin cancer screening significantly more difficult
- Nausea — commonly reported, especially with MT-2
- Cardiovascular effects — MT-2's broad receptor activity raises concerns
- No long-term safety data in healthy populations for cosmetic tanning use
- Not FDA-approved for tanning — any vendor marketing these for tanning is operating outside legal boundaries
Regulatory Status
| Peptide | FDA Status | Pharmacy Available? | Reclassification Expected? |
|---|---|---|---|
| MT-1 (Afamelanotide) | Approved as Scenesse (EPP only) | Specialty pharmacy for EPP | No |
| MT-2 | Not approved | No | No |
Both remain primarily gray market products for non-EPP applications.
How It's Sold
| Source | Form | Availability | Typical Cost |
|---|---|---|---|
| Research Vendors | Lyophilized powder (10mg) | MT-2 common; MT-1 rare | $20-50/vial (MT-2) |
| Specialty Pharmacy | Scenesse (MT-1 implant) | EPP patients only | Very expensive |
| Gray Market | Nasal sprays, pre-mixed vials | Common but risky | Varies widely |
Red Flags Specific to Melanotan
- Nasal sprays — widely sold but bioavailability is poorly established and quality control is minimal
- Pre-mixed "tanning injections" — extremely risky with no quality verification
- Dramatic before/after photos — marketing tactic, not evidence of product quality
- Vendors making specific tanning or sexual enhancement claims
- Products that don't specify whether they contain MT-1 or MT-2
What to Look For on the COA
- HPLC purity — minimum 95%, preferably 98%+
- Mass spectrometry — MT-1: ~1,647 Da; MT-2: ~1,024 Da
- Variant identification — the COA must clearly distinguish MT-1 from MT-2
- Endotoxin testing — standard for injectable research compounds
The cyclic structure of MT-2 makes synthesis more complex than linear peptides. Impurities are more common — always verify purity data before purchasing.
Key Sourcing Tips
- Understand the risk profile — melanotan peptides have more documented side effects than most research peptides
- Never purchase pre-mixed or nasal spray formulations from unverified sources
- If interested in photoprotection for a medical condition, consult a dermatologist about Scenesse
- Always verify your COA specifies which variant (MT-1 or MT-2) you're receiving
- Monitor existing moles closely and maintain regular dermatologist visits for skin checks