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Tools›Compare›Testagen 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
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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
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