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ToolsComparePentapeptide-18 vs Tirzepatide

Pentapeptide-18 vs Tirzepatide

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

Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
GLP-1 / Weight Loss Agonists
Tirzepatide
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.
Tirzepatide is an FDA-approved dual GIP/GLP-1 receptor agonist that produces greater weight loss than semaglutide in head-to-head trials. SURMOUNT-1 trial showed average 21% body weight reduction at 72 weeks at the highest dose. Marketed as Mounjaro (diabetes) and Zepbound (obesity).
Half-Life
Not applicable (topical)
~5 days
Admin Route
Topical
SubQ
Research
Typical Dose
0.005–0.05% in formulation
2.5 mg → 5 mg → 7.5 mg → 10 mg → 12.5 mg → 15 mg
Frequency
Twice daily
Once weekly, subcutaneous
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
  • Average 21% body weight reduction at highest dose (SURMOUNT-1)
  • Superior to semaglutide in head-to-head SURPASS trials
  • Dual GIP/GLP-1 mechanism for enhanced metabolic control
  • Significant reduction in HbA1c for type 2 diabetes
  • Improved cardiovascular risk markers
  • Reduces visceral fat preferentially
  • FDA-approved for T2DM (Mounjaro) and obesity (Zepbound)
  • Weekly dosing
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 during titration)
  • Vomiting
  • Diarrhea or constipation
  • Abdominal pain
  • +3 more
Stacks With