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ToolsCompareTestagen vs GHRP-2

Testagen vs GHRP-2

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

Anti-Aging & Longevity
Testagen
Growth Hormone Peptides
GHRP-2
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.
GHRP-2 is a potent synthetic hexapeptide that stimulates growth hormone release by activating ghrelin receptors in the pituitary and hypothalamus. It produces one of the strongest GH pulses among GHRPs, though unlike Ipamorelin it does cause modest increases in cortisol and prolactin.
Half-Life
Short (minutes); sustained gene-regulatory effects
15–60 minutes
Admin Route
SubQ, Oral
SubQ, Intranasal
Research
Typical Dose
10 mg per day
100–300 mcg
Frequency
Daily for 10–30 days
2–3 times 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
  • Strong GH pulse stimulation
  • Increased IGF-1 levels
  • Enhanced muscle growth and recovery
  • Improved fat metabolism
  • Better sleep quality
  • Increased bone density
  • Enhanced appetite (less pronounced than GHRP-6)
  • Anti-aging effects via GH axis optimization
Side Effects
  • Generally well tolerated
  • Mild injection site reactions
  • No significant endocrine disruption reported at standard doses
  • Increased appetite
  • Water retention
  • Elevated cortisol (modest)
  • Elevated prolactin (modest)
  • +2 more
Stacks With