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ToolsCompareRetatrutide vs Tripeptide-29

Retatrutide vs Tripeptide-29

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

GLP-1 / Weight Loss Agonists
Retatrutide
Skin & CosmeticAnti-Aging & Longevity
Tripeptide-29
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.
Tripeptide-29 is a pro-collagen cosmetic peptide composed of proline, hydroxyproline, and glycine — the core repeating unit of collagen. Applied topically, it signals dermal fibroblasts that collagen degradation has occurred, triggering compensatory new collagen synthesis.
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
0.01-0.1% in formulation
Frequency
Once weekly
Once or 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
  • Stimulates fibroblast collagen synthesis via damage-signal mechanism
  • Reduces fine lines and improves skin smoothness
  • Supports dermal matrix integrity
  • Naturally bioidentical to collagen fragment sequences
  • Well-tolerated in all skin types
  • Synergistic with copper peptides and retinoids
Side Effects
  • Nausea and vomiting (common during titration, similar to semaglutide/tirzepatide)
  • Diarrhea
  • Constipation
  • Heart rate increase (from glucagon receptor agonism)
  • +2 more
  • Excellent tolerability profile
  • No documented significant adverse effects at cosmetic concentrations
  • Rare sensitivity reactions in individuals with peptide allergies
Stacks With