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ToolsCompareTestagen vs Cortagen

Testagen vs Cortagen

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

Anti-Aging & Longevity
Testagen
Anti-Aging & LongevityRecovery & Repair
Cortagen
Summary
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.
Cortagen is a synthetic tetrapeptide (Ala-Glu-Asp-Pro) developed at the St. Petersburg Institute of Bioregulation as a cardioprotective and vascular bioregulator. It stimulates repair of cardiac and vascular tissue, with demonstrated benefits for coronary artery disease, atherosclerosis, and cardiac aging.
Half-Life
Short (minutes); sustained gene-regulatory effects
Short peptide half-life; gene regulatory effects persist beyond peptide clearance
Admin Route
SubQ, Oral
SubQ, IM, Oral
Research
Typical Dose
10 mg per day
10 mg SC or IM daily
Frequency
Daily for 10–30 days
Once daily
Key Benefits
  • 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
  • Cardioprotective — protects cardiac tissue from ischemic damage
  • Promotes cardiac regeneration and repair
  • Improves vascular endothelium function
  • Reduces atherosclerosis progression
  • Anti-aging effect on heart muscle cells
  • Improves cardiac output and exercise capacity
  • Reduces oxidative stress in cardiovascular tissue
  • May reduce arrhythmia frequency
Side Effects
  • Generally well tolerated
  • Mild injection site reactions
  • No significant endocrine disruption reported at standard doses
  • Excellent safety profile
  • Mild injection site reactions
  • Rare: transient hypotension
  • Rare: mild arrhythmia at initiation in cardiac patients
Stacks With