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ToolsCompareSermorelin vs Pentapeptide-18

Sermorelin vs Pentapeptide-18

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

Growth Hormone PeptidesAnti-Aging & Longevity
Sermorelin
Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Summary
Sermorelin is a bioidentical synthetic peptide comprising the first 29 amino acids of naturally occurring GHRH. It is FDA-approved for diagnostic use and widely prescribed off-label for anti-aging, stimulating growth hormone production in a natural pulsatile pattern that mimics the body's own rhythm.
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.
Half-Life
10–20 minutes
Not applicable (topical)
Admin Route
SubQ
Topical
Research
Typical Dose
200–500 mcg
0.005–0.05% in formulation
Frequency
5–7 days per week
Twice daily
Key Benefits
  • Increases energy and vitality
  • Improves body composition (more muscle, less fat)
  • Enhances skin thickness and elasticity
  • Strengthens immune system
  • Improves sleep quality and REM sleep
  • Supports bone density
  • Enhances mental clarity and focus
  • Safer than exogenous HGH — respects natural feedback loops
  • FDA-approved for GH diagnostic use
  • 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
Side Effects
  • Injection site irritation
  • Flushing
  • Headache
  • Dizziness
  • +2 more
  • Generally very well-tolerated topically
  • Rare skin sensitivity or mild irritation
  • Theoretical opioid receptor desensitization with very prolonged high-dose use (not documented cosmetically)
Stacks With