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ToolsCompareGHK-Cu vs Testagen

GHK-Cu vs Testagen

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

Skin & CosmeticRecovery & RepairAnti-Aging & Longevity
GHK-Cu
Anti-Aging & Longevity
Testagen
Summary
GHK-Cu is a naturally occurring copper complex that declines with age. It is one of the most studied anti-aging peptides, known for powerful skin rejuvenation, wound healing, and tissue remodeling effects.
Testagen is a tetrapeptide bioregulator (Lys-Glu-Asp-Gly) developed by Professor Vladimir Khavinson, tissue-specific for the testes. It supports Leydig cell function, normalization of testosterone biosynthesis, and spermatogenic activity. Testagen is used in men's health protocols for age-related testosterone decline, male fertility support, and testicular anti-aging.
Half-Life
2–4 hours
Short (minutes); sustained gene-regulatory effects
Admin Route
SubQ, Topical
SubQ, Oral
Research
Typical Dose
1–3 mg
10 mg per day
Frequency
3–5 times per week
Daily for 10–30 days
Key Benefits
  • Reduces wrinkles and fine lines
  • Improves skin firmness and elasticity
  • Accelerates wound healing
  • Reduces inflammation and oxidative damage
  • Promotes hair growth and thickness
  • Supports collagen and elastin production
  • May improve overall skin health and appearance
  • Resets aged fibroblast behavior
  • Anti-fibrotic — reduces scar tissue formation
  • Supports endogenous testosterone synthesis via Leydig cell normalization
  • Promotes spermatogenesis and sperm quality
  • Anti-aging effects on testicular tissue
  • May attenuate age-related testosterone decline
  • Mechanistically distinct from TRT — does not suppress HPG axis
  • Useful adjunct to Gonadorelin and Kisspeptin-10 in male hormonal protocols
  • Supports male fertility without exogenous hormone replacement
Side Effects
  • Temporary blue-green discoloration at injection site (from copper — harmless)
  • Post-injection sting (brief)
  • Skin irritation with topical use (rare)
  • Generally well tolerated
  • Mild injection site reactions
  • No significant endocrine disruption reported at standard doses
Stacks With