Testagen vs Alpha-GPC
Side-by-side comparison of key properties, dosing, and research.
- 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.
- Alpha-GPC is the most bioavailable form of choline, readily crossing the blood-brain barrier to rapidly increase acetylcholine levels. It enhances cognitive performance, supports GH secretion, and is used as an essential complement to many nootropic peptides (especially those that increase acetylcholine demand like Noopept and Dihexa).
- Half-Life
- Short (minutes); sustained gene-regulatory effects
- ~4–6 hours
- Admin Route
- SubQ, Oral
- Oral, SubQ
- Research
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- Typical Dose
- 10 mg per day
- 300–600 mg
- Frequency
- Daily for 10–30 days
- 1–2x 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
- Rapidly raises brain acetylcholine levels
- Enhances memory formation and recall
- Prevents headaches from nootropic peptides (choline donor)
- Stimulates growth hormone secretion (modest)
- Improves attention and processing speed
- Neuroprotective in Alzheimer's and cognitive decline
- Approved in Europe for Alzheimer's therapy
- Enhances power output in athletes (pre-workout)
- Side Effects
- Generally well tolerated
- Mild injection site reactions
- No significant endocrine disruption reported at standard doses
- Headache (paradoxically, from excess acetylcholine at very high doses)
- Nausea at doses > 1200 mg
- Dizziness
- Fatigue at high doses
- +1 more
- Stacks With
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