Retatrutide vs Melanotan I
A detailed comparison to help you understand the differences and choose the right peptide for your research goals.
Retatrutide
Retatrutide is an investigational triple agonist targeting GIP, GLP-1, and glucagon receptors. Phase 2 trials showed unprecedented weight loss of up to 24% at 48 weeks, making it potentially the most effective obesity treatment studied.
Full details →Melanotan I
Melanotan I (afamelanotide) is a synthetic analog of alpha-melanocyte-stimulating hormone (α-MSH). It is FDA-approved as Scenesse for erythropoietic protoporphyria (EPP), a rare genetic disorder causing severe sun sensitivity.
Full details →Side-by-Side Comparison
| Aspect | Retatrutide | Melanotan I |
|---|---|---|
| Mechanism | Triple receptor activation provides complementary metabolic effects: GLP-1 and GIP reduce appetite and improve insulin sensitivity, while glucagon receptor activation increases energy expenditure and promotes hepatic fat oxidation. | Binds to melanocortin 1 receptors (MC1R) on melanocytes, stimulating eumelanin production. This increases skin pigmentation and provides photoprotection without UV exposure. |
| Typical Dosage | Clinical trials used doses from 1mg to 12mg weekly. Optimal dosing still being determined in ongoing Phase 3 trials. | Clinical: 16mg implant every 2 months. Research protocols for tanning typically use 0.5-1mg daily for loading, then maintenance dosing. |
| Administration | Subcutaneous injection once weekly. Currently only available through clinical trials - not yet FDA approved. | FDA-approved form is a subcutaneous implant. Research use involves subcutaneous injection. Often combined with minimal UV exposure to enhance results. |
| Side Effects | Similar GI effects to other incretin-based therapies: nausea, diarrhea, vomiting, constipation. Dose-dependent severity. | Nausea (especially initially), facial flushing, fatigue, headache, and darkening of existing moles or freckles. |
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