Melanotan II
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Route(s): Subcutaneous
Typical vial sizes: 10 mg
Dosing window: Pre-UV / Pre-Bed
Receptor / target: MC1R; MC4R
Properties: Not stated
Pre-mixed: No
Site-sourced protocols
Standard Protocol
| Timeframe | Dose | Notes |
|---|---|---|
| Weeks 1-2 (Loading) | 250mcg daily | Administer pre-bed to sleep through initial nausea. |
| Weeks 3+ (Maintenance) | 500mcg twice weekly | Requires UV exposure. |
Site-provided protocol; not independently verified as label dosing unless graded otherwise on this page.
Alternative: Micro-Dosing
| Timeframe | Dose | Notes |
|---|---|---|
| Weeks 1+ | 100mcg daily | Low and slow approach. Prevents spontaneous erections and avoids the intense nausea completely. |
Site-provided alternative protocol; not an approved-label regimen unless graded otherwise on this page.
Alternative Titration 2
| Timeframe | Dose | Notes |
|---|---|---|
| Week 1 | 250 mcg 1x Daily | |
| Week 2 | 500 mcg 1x Daily | |
| Week 3 | 750 mcg 1x Daily | |
| Weeks 4-8 | 1000 mcg 1x Daily | |
| Weeks 8+ | 500-1000 mcg 1-2× weekly |
Site-provided alternative protocol; not an approved-label regimen unless graded otherwise on this page.
Protocol logic check
Independent evidence
Regulatory status: unapproved or compounded peptide with FDA safety risk flag
Storage
No independently verified storage guidance found. Treat any site-sourced storage claim as unverified, and see the general storage guidance in the FAQ.
Contraindications (site-sourced)
- Personal or family history of melanoma: MT-II's cyclic structure produces higher-affinity MC1R/MC5R agonism than MT-I with greater theoretical oncogenic acceleration potential in cells carrying melanocytic mutations; absolute contraindication; the most critically enforced safety boundary in Category VII. Site-only / unverified
- Dysplastic nevus syndrome or multiple atypical moles: highest-risk pre-malignant melanocytic context; absolute contraindication. Site-only / unverified
- History of any skin cancer: indicates compromised photoprotective/DNA repair phenotype; contraindicated. Site-only / unverified
- Cardiovascular disease (recent MI, unstable angina, severe hypertension): MT-II's substantial MC4R-mediated sympathetic activation produces significant transient blood pressure elevation and tachycardia; the magnitude is greater than PT-141 per mg due to MT-II's higher binding affinity. Site-only / unverified
- Concurrent use with Melanotan I: additive MC1R agonism produces no proportional tanning benefit while stacking the full side effect profiles of both compounds; absolute contraindication. Site-only / unverified
- Concurrent use with PDE5 inhibitors (sildenafil, tadalafil, vardenafil) in subjects with cardiovascular disease: the combination of MC4R-driven vasodilation from MT-II with PDE5 inhibitor vasodilation can produce severe hypotension in subjects with cardiovascular risk. Site-only / unverified
- Known hypersensitivity to MT-II or cyclic alpha-MSH analogs. Site-only / unverified
- Pregnancy: not established as safe; MC4R/HPT axis interactions during pregnancy are not characterized. Site-only / unverified
- Breastfeeding: no safety data. Site-only / unverified
- History of priapism or conditions predisposing to prolonged erection (sickle cell disease, leukemia, multiple myeloma): MT-II's potent MC4R-driven spontaneous erection activity is a direct risk in these populations. Site-only / unverified
- Active psychiatric conditions on antipsychotics or mood stabilizers: MC4R dopaminergic overlap with antipsychotic targets. Site-only / unverified
Side effects (site-sourced)
- Intense nausea: the most expected, consistent, and severe adverse effect; occurs in the majority of subjects at doses of 250mcg and above; caused by potent MC4R activation in the area postrema; onset 30-60 minutes post-injection; duration 1-4 hours; pre-bed dosing during loading phase is the primary management strategy; significantly more severe than MT-I or PT-141 per microgram due to MT-II's higher MC4R binding affinity. Site-only / unverified
- Spontaneous erections: a consistent pharmacological consequence of MC4R hypothalamic activation at standard doses; present in the majority of male subjects; cannot be reliably avoided except through micro-dosing; a defining pharmacological property that distinguishes MT-II from MT-I. Site-only / unverified
- Darkening of existing moles and nevi: predictable MC1R-driven eumelanogenesis in all existing melanocytic lesions; all moles must be documented and monitored; any atypical change warrants immediate dermatological evaluation. Site-only / unverified
- Facial flushing: intense; MC4R/MC3R-driven cutaneous vasodilation; immediate onset with injection; lasts 1-3 hours; more pronounced than MT-I. Site-only / unverified
- New nevus formation: documented in research populations with sustained MT-II use; direct consequence of MC1R-driven melanocyte proliferation. Site-only / unverified
- Priapism (prolonged erection): rare but serious; requires emergency medical intervention if erection persists beyond 4 hours; higher risk with MT-II than PT-141 due to greater MC4R potency. Site-only / unverified
- Increased libido and spontaneous sexual arousal: a pharmacological effect rather than an adverse event in the sexual health context; problematic in the wrong setting and in subjects not expecting this effect. Site-only / unverified
- Transient blood pressure and heart rate elevation: MC4R sympathetic activation produces meaningful hemodynamic changes; more pronounced than PT-141; monitor in subjects with any cardiovascular risk factors. Site-only / unverified
- Appetite suppression and weight loss: MC4R hypothalamic agonism suppresses appetite; a secondary effect that becomes clinically significant with prolonged high-dose use. Site-only / unverified
- Yawning: a consistent and early signal of MC4R activation onset; typically precedes nausea and arousal effects by 15-30 minutes. Site-only / unverified
- Injection site hyperpigmentation: localized darkening at repeated subcutaneous injection sites from local MC1R activation in underlying tissue. Site-only / unverified
- Fatigue and post-injection lethargy: as acute MC4R activity resolves, a rebound fatigue phase is common; manageable with pre-bed dosing. Site-only / unverified
- MC1R/MC4R receptor desensitization: with high-frequency dosing; the maintenance protocol (twice weekly) is the standard mitigation. Site-only / unverified
Compatibility
The relationships below come from the source site's internal engine and were not verified independently. Treat them as a starting point for a conversation with a clinician. They carry no safety guarantee.
Reported synergistic:
Reported contraindicated combinations: