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ToolsCompareThymalin vs Alpha-GPC

Thymalin vs Alpha-GPC

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

Immune SupportAnti-Aging & Longevity
Thymalin
Cognitive Enhancement
Alpha-GPC
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.
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
Not well characterized as a complex extract; individual peptides have varying kinetics
~4–6 hours
Admin Route
SubQ, IM
Oral, SubQ
Research
Typical Dose
10 mg IM or SC daily
300–600 mg
Frequency
Once daily
1–2x daily
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
  • 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
  • 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)
  • Headache (paradoxically, from excess acetylcholine at very high doses)
  • Nausea at doses > 1200 mg
  • Dizziness
  • Fatigue at high doses
  • +1 more
Stacks With