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ToolsComparePentapeptide-18 vs Dulaglutide

Pentapeptide-18 vs Dulaglutide

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

Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
GLP-1 / Weight Loss Agonists
Dulaglutide
Summary
Pentapeptide-18 (Leuphasyl) is a synthetic pentapeptide that mimics the sequence of enkephalin, an endogenous neuropeptide. It acts on neuronal pain receptors in facial muscles to reduce muscle contraction intensity and depth of expression lines, functioning similarly to Argireline (Acetyl Hexapeptide-3) but via a different receptor mechanism.
Dulaglutide (brand name Trulicity) is a once-weekly GLP-1 receptor agonist approved by the FDA for type 2 diabetes management and cardiovascular risk reduction. It consists of two GLP-1 analog chains fused to a modified IgG4 Fc fragment, extending its half-life to approximately 5 days. While primarily a diabetes medication, it produces meaningful weight loss and has established cardiovascular outcomes data from the REWIND trial.
Half-Life
Not applicable (topical)
~5 days
Admin Route
Topical
SubQ
Research
Typical Dose
0.005–0.05% in formulation
0.75 mg → 1.5 mg
Frequency
Twice daily
Once weekly
Key Benefits
  • Reduces depth of expression lines (forehead, crow's feet, glabellar)
  • Inhibits acetylcholine release for muscle-relaxing effect
  • Complementary mechanism to Argireline for enhanced anti-wrinkle activity
  • Reversible and well-tolerated
  • No risk of systemic paralysis at cosmetic concentrations
  • Suitable for daily use in serums and creams
  • FDA-approved for type 2 diabetes
  • Once-weekly subcutaneous dosing via auto-injector pen
  • Reduces HbA1c by approximately 1.1–1.6%
  • Modest weight loss of 1.5–3 kg at approved doses
  • Demonstrated cardiovascular risk reduction (REWIND trial)
  • Established long-term safety profile
  • Renal protective effects in CKD
Side Effects
  • Generally very well-tolerated topically
  • Rare skin sensitivity or mild irritation
  • Theoretical opioid receptor desensitization with very prolonged high-dose use (not documented cosmetically)
  • Nausea (most common, typically transient)
  • Diarrhea
  • Vomiting
  • Decreased appetite
  • +3 more
Stacks With