Melanocortin Investigational

Melanotan II

Also known as: MT-2, MT-II, Melanotan 2

A non-selective melanocortin agonist that produces UV-free tanning, enhances libido, and suppresses appetite through MC1R-MC5R receptor activation.

Popularity A
Class Melanocortin Receptor Agonist
Half-Life ~33 minutes (but effects persist 6-8 hours)
Form Lyophilized powder, Nasal spray
View Vendors → Jump to Dosing ↓
Melanotan II C50H69N15O9
Research-Backed User Reports Sourced Updated Mar 2026
// Overview

What is Melanotan II?

Melanotan II (MT-2) is a synthetic cyclic analog of alpha-melanocyte-stimulating hormone (α-MSH) developed at the University of Arizona. It acts on melanocortin receptors MC1R through MC5R, producing a range of effects including skin pigmentation (tanning), sexual arousal, appetite suppression, and potential fat loss.

Originally investigated as a potential sunless tanning agent to reduce melanoma risk, Melanotan II gained widespread underground popularity for its cosmetic tanning effects and sexual function benefits. Its non-selective melanocortin receptor activation is responsible for both its diverse benefits and side effect profile.

While never approved for clinical use, MT-2 remains one of the most widely used cosmetic peptides globally. Its derivative PT-141 (bremelanotide) — which isolated the sexual function pathway — was eventually FDA-approved as Vyleesi for female hypoactive sexual desire disorder.

Looking for the best vendor deals?

Compare prices across 10+ peptide and anabolic vendors. Find the best quality at the lowest price.

Compare Vendors
// How It Works

How Melanotan II Works

Melanotan II is a non-selective melanocortin receptor agonist:

  1. MC1R (skin) — Stimulates melanocytes to produce eumelanin (dark pigment), resulting in skin tanning without UV exposure. This is the primary cosmetic effect.
  2. MC3R/MC4R (brain) — Activation of central melanocortin receptors in the hypothalamus produces appetite suppression (MC4R) and sexual arousal/erectile function (MC3R/MC4R). The MC4R pathway is what led to PT-141 development.
  3. MC5R (sebaceous glands) — May affect sebum production and exocrine function.
  4. Cross-receptor activity — The non-selective nature means MT-2 produces all these effects simultaneously, unlike PT-141 which was designed for MC4R selectivity.
// Dosage Protocols

Dosage Information (User-Reported)

Disclaimer: Dosage information is compiled from user reports and published research. This is not medical advice. Consult a healthcare professional before use.
Level Dose Frequency Duration
Loading 250-500 mcg Daily 10-14 days
Maintenance (Tanning) 500 mcg 2x per week As needed
Libido Only 250 mcg As needed (30-60 min before) As needed

What to Expect

Day 1-3

Nausea is common with first few doses (take with food or start at 100mcg). Facial flushing. Some report mild erections or arousal.

Week 1-2

Existing moles/freckles darken first. Gradual skin bronzing begins. Appetite noticeably reduced. Libido enhanced.

Week 2-4

Visible tan develops even with minimal UV. Skin continues darkening. Sexual effects peak. Appetite suppression strong.

Maintenance

Tan maintained with infrequent dosing (1-2x/week). Effects persist between doses. Moles may darken permanently.

Common Stacks

PT-141

Targeted Libido

For users wanting sexual effects without additional tanning — use PT-141 for isolated MC4R activation

BPC-157

Skin Health

Supports skin healing and reduces potential for injection site irritation

GHK-Cu

Skin Quality

Combines tanning with copper peptide's collagen-boosting and skin-repair effects

// Preparation

Reconstitution & Storage

Reconstitute with bacteriostatic water. For a 10mg vial, add 2mL BAC water for 5mg/mL (500mcg per 0.1mL / 10 units on insulin syringe).

Inject water slowly. Do not shake. Swirl gently until dissolved.

Store refrigerated. Stable for up to 30 days reconstituted.

Storage: Lyophilized: room temperature or refrigerated. Reconstituted: refrigerate 2-8°C, use within 30 days.

Ready to source Melanotan II?

Compare prices across verified vendors. Find the best purity at the lowest price.

Compare Vendors →
// Safety Profile

Side Effects & Safety

Potential Side Effects

  • ! Nausea (very common with initial doses — dose-dependent)
  • ! Facial flushing
  • ! Darkening of existing moles and freckles
  • ! Spontaneous erections (in males)
  • ! Fatigue and yawning
  • ! Injection site soreness
  • ! Appetite suppression (can be excessive)
  • ! New mole development (monitor for atypical moles)
  • ! Headache

Contraindications

  • ⚠ History of melanoma or atypical mole syndrome
  • ⚠ Pregnancy or breastfeeding
  • ⚠ Cardiovascular disease (affects blood pressure)
  • ⚠ Known allergy to melanocortin peptides

Legal & Regulatory Status

Not FDA-approved. Banned for sale as a consumer product in several countries (Australia, UK). Available as a research chemical from peptide vendors. Not a controlled substance in the US but regulatory status varies internationally.

// Research

Published Research

// Where to Buy

Top Vendors for Melanotan II

Ranked by our review scores. All vendors are independently tested.

B+
Read Review Visit Vendor →
B+
Read Review Visit Vendor →
B+
Read Review Visit Vendor →
// Related Compounds

Other Melanocortin Guides

Cagrilintide

A long-acting amylin analog that amplifies weight loss when paired with semaglutide — the amylin component of CagriSema's…

Read Guide →

BPC-157 Arginate (Oral)

The oral form of BPC-157 — gastric-acid stable and designed for direct GI tract healing. No injections needed…

Read Guide →

TB-500 Fragment

A concentrated fragment of Thymosin Beta-4 focused on the core actin-binding domain — smaller molecule, targeted tissue repair.

Read Guide →

Stay informed on Melanotan II.

New research, dosage updates, and vendor deals. Straight to your inbox.

Free forever. No spam. Unsubscribe anytime.

This content is for informational and educational purposes only. Melanotan II is sold for research purposes. Never Natty does not condone or encourage the use of any substance in violation of any laws. Consult a healthcare professional before using any compound discussed on this site.