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ToolsCompareGHRP-2 vs Testagen

GHRP-2 vs Testagen

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

Growth Hormone Peptides
GHRP-2
Anti-Aging & Longevity
Testagen
Summary
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.
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
15–60 minutes
Short (minutes); sustained gene-regulatory effects
Admin Route
SubQ, Intranasal
SubQ, Oral
Research
Typical Dose
100–300 mcg
10 mg per day
Frequency
2–3 times daily
Daily for 10–30 days
Key Benefits
  • 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
  • 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
  • Increased appetite
  • Water retention
  • Elevated cortisol (modest)
  • Elevated prolactin (modest)
  • +2 more
  • Generally well tolerated
  • Mild injection site reactions
  • No significant endocrine disruption reported at standard doses
Stacks With