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ToolsComparePentapeptide-18 vs Gonadorelin

Pentapeptide-18 vs Gonadorelin

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

Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Sexual Health & LibidoAnti-Aging & Longevity
Gonadorelin
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.
Gonadorelin is the synthetic form of endogenous GnRH (gonadotropin-releasing hormone). It stimulates the pituitary to release LH and FSH, maintaining testicular function and testosterone production. Widely used alongside TRT to prevent testicular atrophy and preserve fertility.
Half-Life
Not applicable (topical)
~2–4 minutes (extremely short); pulsatile dosing required to avoid desensitization
Admin Route
Topical
SubQ, Intranasal
Research
Typical Dose
0.005–0.05% in formulation
100 mcg
Frequency
Twice daily
Twice daily (every 12 hours)
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
  • Maintains testicular size during TRT
  • Preserves fertility and sperm production during testosterone use
  • Stimulates endogenous LH/FSH production
  • Maintains HPG axis function during exogenous hormone use
  • Used for HCG-free TRT protocols
  • Helps restart natural testosterone production (PCT)
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)
  • Injection site reactions
  • Headache
  • Nausea at initiation
  • Tachycardia (rare)
  • +1 more
Stacks With