Thymalin vs Testagen
Side-by-side comparison of key properties, dosing, and research.
- Summary
- Thymalin is a polypeptide complex isolated from calf thymus glands (developed by the Russian Gerontology Institute), shown to restore immune function, extend lifespan, and reverse thymic involution. Clinical studies demonstrate improved immune parameters and up to 40% reduction in mortality in elderly patients.
- 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
- Not well characterized as a complex extract; individual peptides have varying kinetics
- Short (minutes); sustained gene-regulatory effects
- Admin Route
- SubQ, IM
- SubQ, Oral
- Research
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- Typical Dose
- 10 mg IM or SC daily
- 10 mg per day
- Frequency
- Once daily
- Daily for 10–30 days
- Key Benefits
- Restores thymic function and T-cell immunity
- Extends healthy lifespan (documented in long-term studies)
- Reduces infectious disease incidence in elderly
- Normalizes immune parameters in immunodeficiency
- Anti-tumor immune surveillance
- Improves vaccine response in elderly
- Reduces cardiovascular mortality (40% in landmark Russian study)
- Normalizes neuroendocrine function
- 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
- Very well tolerated in decades of Russian clinical use
- Mild injection site reactions
- Rare: mild allergic reaction (natural extract)
- Transient flu-like symptoms on initiation (immune activation)
- Generally well tolerated
- Mild injection site reactions
- No significant endocrine disruption reported at standard doses
- Stacks With
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