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Melanotan II

Hormone Regulation & Endocrine Support

Melanotan II is a synthetic melanocortin peptide that increases melanin production and stimulates sexual arousal. It binds MC1R for tanning and MC4R for libido enhancement, and has been studied for its effects on skin pigmentation and sexual arousal in preclinical models and limited human trials. Unlike MT-1, it has central nervous system activity.

Reconstitute
2 mL BAC + 10mg vial
50 mcg/unit
Daily Range
0.25–1 mg Subcutaneous (SQ)
As needed or daily during tanning phase
Standard Dose
0.5 mg
Cycle
4–8 weeks
then reassess
Melanotan IIMC4R agonistsexual peptidetanning peptidemelanocortin

Dosing & Reconstitution Guide

Preclinical and early human studies used 0.25–1.0 mg via subcutaneous injection. Side effects and long-term safety are not fully understood.

Standard / Gradual Approach

standard
PhaseDoseVolume
Week 1250mcg
Week 2500mcg
Week 3750mcg
Week 41000mcg

Protocol Summary

Subcutaneous (SQ): As needed or daily during tanning phase · Dose range 0.25–1 mg with gradual titration
Cycle Length: 4–8 weeks typical; reassess before extending

Frequency & Cycling

SubQ Injection

Inject 0.25–0.5 mg daily for 10–14 days for tanning phase. For sexual effects, use 0.5–1 mg as needed. Do not exceed 1 mg/day without guidance.

🧪 Quick Start

BAC Water
2 mL

Potential Benefits & Use Cases

Melanotan II is not approved for tanning or libido enhancement. Research use only.
Increases skin pigmentation (tanning) without UV exposure requirement (human trial)
Tanning effects observable after 5–10 daily injections (human trial)
Enhances sexual desire in 68% of doses vs 19% placebo; induces erections via MC4R activation (human trial)
Maintenance dosing (1–2× weekly) sustains pigmentation after loading (human trial)
Clinical data Strong preclinical Limited data

Mechanism of Action

→Non-selectively binds to melanocortin receptors (MC1R, MC3R, MC4R)
→Stimulates melanin synthesis in melanocytes for skin darkening
→Activates central arousal pathways through MC4R in hypothalamus
→May modulate appetite and fat metabolism through MC3R

Lifestyle & Optimization

timing

Inject before UV exposure for optimal melanin response. Start with low dose.

diet

Maintain adequate hydration (nausea and appetite suppression may occur).

exercise

Regular exercise 3–4 times weekly.

sleep

Moderate sun exposure of 10–15 minutes daily. Always use appropriate sunscreen. Monitor moles and skin regularly.

Peptide Research & Preclinical Studies

Evidence-Based Research Findings

Study TitleType
PubMed — Dorr RT et al. (1996) — Phase I clinical studyReference
International Peptide Society — Melanotan II MonographReference
DermNet NZ — Melanotan II InformationReference
PubMed — Nelson ME et al. (2012) — Case reportReference
RxList — Melanotan-II Uses and DosingReference
Health Service Executive (HSE) Ireland — Advice on tanning agentsReference

Side Effects & Safety

Common Side Effects

• Nausea (dose-dependent, most common at higher doses)
• Facial flushing, increased skin warmth
• Reduced appetite and mild fatigue
• Spontaneous erections and increased libido in men
• Transient HR and BP increases at higher doses

Contraindications & Warnings

• Not FDA-approved; use carries regulatory and safety risks
• Severe toxicity at 6 mg dose (rhabdomyolysis reported)
• May alter mole pigmentation; case reports of melanoma — theoretical melanoma concerns

🧮 Dose Calculator

Concentration
50.0
mcg/unit
Draw Volume
10
units (0.100 mL)
For a 500 mcg dose, draw 10 units on a U-100 insulin syringe
🧬

Bioavailability & Absorption

SubQ Injection
High systemic uptake; effects appear within 1–4 hours post-injection
Oral Administration
Not viable orally
Half-Life
33–38 minutes
Degradation
Cleared by liver and kidneys
Tissue Specificity
Melanocytes, hypothalamus, and CNS sexual centers
⚗️

Peptide Details

Molecular Weight
1025.2
Formula
C50H69N15O9
Sequence
Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2
⚖️

Legal Status & Regulatory

RegionStatus
FDANot Approved
EUNot Approved
AustraliaPrescription Only
CanadaNot Approved

Storage Instructions

Lyophilized (Powder)
Store lyophilized powder at 2-8°C away from light
Reconstituted (Mixed)
After reconstitution, maintain at 2-8°C and use within 28 days. Protect from UV light exposure.