Nonapeptide-1 vs Retatrutide
Side-by-side comparison of key properties, dosing, and research.
Skin & Cosmetic
Nonapeptide-1GLP-1 / Weight Loss Agonists
Retatrutide- Summary
- Nonapeptide-1 is a synthetic 9-amino acid peptide that inhibits melanin production by blocking α-MSH (alpha-melanocyte stimulating hormone) receptor binding. Used in cosmetic formulations for skin lightening and evening skin tone, it is particularly effective for UV-induced and hormonal hyperpigmentation.
- Retatrutide is an investigational triple receptor agonist targeting GLP-1, GIP, and glucagon receptors simultaneously. Phase 2 trials showed an unprecedented average 24% body weight reduction at 48 weeks — exceeding any approved medication to date. It is in Phase 3 trials as of 2024.
- Half-Life
- Not applicable (topical)
- ~10–12 days
- Admin Route
- Topical
- SubQ
- Research
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- Typical Dose
- 0.05–0.5% concentration in formulation
- 0.5 mg → 1 mg → 2 mg → 4 mg → 8 mg → 12 mg
- Frequency
- Twice daily
- Once weekly
- Key Benefits
- Inhibits UV-induced tanning and hyperpigmentation
- Reduces hormonal melasma
- Evens skin tone at receptor level
- Well-tolerated with minimal irritation
- Complementary to tyrosinase inhibitors for enhanced brightening
- Reduces post-inflammatory hyperpigmentation
- ~24% body weight reduction at 48 weeks in Phase 2 (highest dose)
- Superior to both semaglutide and tirzepatide in early trial comparisons
- Triple receptor mechanism addresses multiple obesity pathways
- Significant reduction in liver fat (MASH/NAFLD indication being studied)
- Improved cardiovascular and metabolic markers
- Once-weekly dosing
- Potential for greatest weight loss of any currently investigated compound
- Side Effects
- Generally very well-tolerated
- Rare contact sensitivity in susceptible individuals
- Theoretical risk of excessive depigmentation with prolonged high-concentration use
- Nausea and vomiting (common during titration, similar to semaglutide/tirzepatide)
- Diarrhea
- Constipation
- Heart rate increase (from glucagon receptor agonism)
- +2 more
- Stacks With
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