Melanotan I

At a glance

Standard Protocol

Sexual-health protocols are usually acute pathway protocols, so timing and contraindications matter more than chronic escalation. Cardiovascular disease, blood pressure drugs, nitrates, priapism risk, and nausea are key filters. Entry context: target (MC1R; MC4R); route Subcutaneous; timing Pre-UV. Unapproved or source-dataset dosing tables are hypotheses, not recommendations. Compatibility is conditional: a reasonable solo compound can become inappropriate once a contraindicated partner is added.

• Darkening of existing moles, nevi, and freckles: the most commonly observed and predictable effect; MC1R activation drives eumelanin production in all existing melanocytic lesions proportionally to their baseline MC1R expression; most pronounced in fair-skinned individuals with numerous existing moles; all moles should be photographed and monitored for atypical changes.
• Mild flushing: MC4R is minimally activated by MT-I at standard doses but not completely absent; mild transient flushing occurs in a minority of subjects particularly at higher loading doses.
• Mild nausea: rare and dose-dependent; the near-absence of nausea compared to Melanotan II is the defining pharmacological advantage of MT-I's MC1R selectivity; only occurs at high doses that produce some MC4R spillover.
• New nevus formation: afamelanotide has been associated in clinical EPP trials with the formation of new melanocytic nevi (moles); this is a direct consequence of MC1R-driven melanocyte proliferation and differentiation; all new lesions should be evaluated by a dermatologist.
• Injection site reactions: mild erythema, tenderness, and bruising at the subcutaneous injection site.
• Headache: uncommon; mild; mechanism not fully characterized; more likely at higher loading doses.
• Skin hyperpigmentation beyond intended areas: areas of existing hyperpigmentation (scars, sun spots, birthmarks) may darken disproportionately as their melanocyte density responds to systemic MC1R agonism.
• Spontaneous erections (rare, dose-dependent): at doses above 1.5-2mg, some MC4R activation does occur; spontaneous erections have been reported at higher MT-I doses though far less frequently than with MT-II.
• Transient appetite suppression: minimal MC4R hypothalamic activity may produce mild anorexigenic effects at higher doses.

• Personal or family history of melanoma: MC1R activation drives melanocyte proliferation and MITF-mediated transcriptional programs that overlap with melanoma pathogenesis; any existing oncogenic mutation in melanocytes could be accelerated; absolute contraindication.
• History of any skin cancer (basal cell carcinoma, squamous cell carcinoma): while non-melanocytic skin cancers do not involve MC1R-driven pathways directly, the history indicates a compromised UV-protection/DNA repair phenotype where additional melanocyte stimulation is inadvisable.
• Dysplastic nevus syndrome or multiple atypical moles: the presence of numerous atypical melanocytic lesions with existing dysplastic changes represents the highest pre-malignant risk context for MC1R agonism; absolute contraindication.
• BRAF V600E mutation carrier or known melanocytic oncogenic mutations: any confirmed oncogenic mutation in melanocyte lineage cells makes MC1R-driven proliferation stimulation dangerous.
• Concurrent use with Melanotan II: MT-I and MT-II share MC1R activity as their pigmentation mechanism; co-administration produces additive/redundant MC1R stimulation without proportional additional benefit while combining the side effect profiles of both; these compounds are contraindicated together.
• Known hypersensitivity to afamelanotide, alpha-MSH-derived peptides, or formulation excipients.
• Pregnancy: melanocyte stimulation and the hormonal context of pregnancy interaction are not established as safe.
• Breastfeeding: no safety data.
• Active or recent immunosuppression: MC1R has immunomodulatory activity; interaction with immunosuppressed states is not fully characterized.

Synergistic / related

• https://the source dataset.com/peptide-codex.php
• https://www.fda.gov/drugs/guidance-compliance-regulatory-information/human-drug-compounding
• https://pubmed.ncbi.nlm.nih.gov/?term=Melanotan+I