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ToolsCompareAHK-Cu vs Testagen

AHK-Cu vs Testagen

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

Skin & CosmeticAnti-Aging & Longevity
AHK-Cu
Anti-Aging & Longevity
Testagen
Summary
AHK-Cu is a copper tripeptide composed of alanine, histidine, and lysine chelated to copper. Distinct from GHK-Cu, AHK-Cu exhibits strong affinity for hair follicle receptors and demonstrates potent hair growth stimulation alongside wound healing and skin regeneration properties.
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
Hours (topical, variable by formulation)
Short (minutes); sustained gene-regulatory effects
Admin Route
Topical, Scalp application, Subcutaneous (research)
SubQ, Oral
Research
Typical Dose
0.01–0.1% concentration
10 mg per day
Frequency
Once or twice daily
Daily for 10–30 days
Key Benefits
  • Stimulates hair follicle growth and reduces shedding
  • Increases dermal papilla cell proliferation
  • Promotes wound healing and skin regeneration
  • Antioxidant protection via superoxide dismutase activation
  • Improves skin elasticity and firmness
  • Supports collagen and elastin production
  • 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
  • Generally well-tolerated topically
  • Mild scalp irritation or redness in sensitive individuals
  • Possible temporary hair shedding phase at treatment initiation
  • Copper accumulation with excessive systemic use (rare)
  • Generally well tolerated
  • Mild injection site reactions
  • No significant endocrine disruption reported at standard doses
Stacks With