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ToolsCompareGonadorelin vs Pentapeptide-18

Gonadorelin vs Pentapeptide-18

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

Sexual Health & LibidoAnti-Aging & Longevity
Gonadorelin
Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Summary
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.
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
~2–4 minutes (extremely short); pulsatile dosing required to avoid desensitization
Not applicable (topical)
Admin Route
SubQ, Intranasal
Topical
Research
Typical Dose
100 mcg
0.005–0.05% in formulation
Frequency
Twice daily (every 12 hours)
Twice daily
Key Benefits
  • 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)
  • 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 reactions
  • Headache
  • Nausea at initiation
  • Tachycardia (rare)
  • +1 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