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ToolsComparePentapeptide-18 vs AOD-9604

Pentapeptide-18 vs AOD-9604

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

Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Fat Loss & Metabolic
AOD-9604
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.
AOD-9604 is a modified fragment of human growth hormone (residues 177-191) with an additional tyrosine residue that significantly enhances bioavailability. Originally developed as an anti-obesity drug by Metabolic Pharmaceuticals, it stimulates lipolysis and inhibits lipogenesis without the diabetogenic effects of full GH.
Half-Life
Not applicable (topical)
30-45 minutes injectable; longer with nasal spray formulation
Admin Route
Topical
SubQ, Intranasal, Oral
Research
Typical Dose
0.005–0.05% in formulation
300-600 mcg
Frequency
Twice daily
Once daily
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
  • Selective fat loss without anabolic side effects
  • No effect on blood glucose or insulin resistance
  • Improved bioavailability over Fragment 176-191
  • GRAS (Generally Recognized As Safe) status in Australia
  • Potential cartilage repair and anti-inflammatory properties
  • Does not suppress natural GH production
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)
  • Localized injection site reactions
  • Headache (rare)
  • Hypoglycemia risk in combination with insulin (very rare)
Stacks With