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ToolsComparePalmitoyl Dipeptide-6 vs Retatrutide

Palmitoyl Dipeptide-6 vs Retatrutide

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

Skin & CosmeticAnti-Aging & Longevity
Palmitoyl Dipeptide-6
GLP-1 / Weight Loss Agonists
Retatrutide
Summary
Palmitoyl Dipeptide-6 is a synthetic dipeptide (lysine-threonine) with a palmitoyl fatty acid tail, designed to penetrate the skin barrier and stimulate the extracellular matrix components essential for skin firmness. It activates fibronectin and type IV collagen synthesis, improving skin density and firmness particularly in mature or sagging skin.
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
Typical Dose
0.005–0.05% in formulation
0.5 mg → 1 mg → 2 mg → 4 mg → 8 mg → 12 mg
Frequency
Once or twice daily
Once weekly
Key Benefits
  • Increases skin firmness and density
  • Stimulates fibronectin and collagen IV production
  • Strengthens the dermal-epidermal junction
  • Reduces skin sagging in mature skin
  • Improves skin texture and smoothness
  • Supports extracellular matrix integrity
  • ~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 well-tolerated
  • Rare mild skin irritation in sensitive individuals
  • No known systemic effects at cosmetic concentrations
  • Nausea and vomiting (common during titration, similar to semaglutide/tirzepatide)
  • Diarrhea
  • Constipation
  • Heart rate increase (from glucagon receptor agonism)
  • +2 more
Stacks With