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ToolsCompareRetatrutide vs Nonapeptide-1

Retatrutide vs Nonapeptide-1

Side-by-side comparison of key properties, dosing, and research.

GLP-1 / Weight Loss Agonists
Retatrutide
Skin & Cosmetic
Nonapeptide-1
Summary
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.
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.
Half-Life
~10–12 days
Not applicable (topical)
Admin Route
SubQ
Topical
Research
Typical Dose
0.5 mg → 1 mg → 2 mg → 4 mg → 8 mg → 12 mg
0.05–0.5% concentration in formulation
Frequency
Once weekly
Twice daily
Key Benefits
  • ~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
  • 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
Side Effects
  • Nausea and vomiting (common during titration, similar to semaglutide/tirzepatide)
  • Diarrhea
  • Constipation
  • Heart rate increase (from glucagon receptor agonism)
  • +2 more
  • Generally very well-tolerated
  • Rare contact sensitivity in susceptible individuals
  • Theoretical risk of excessive depigmentation with prolonged high-concentration use
Stacks With