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ToolsCompareAlpha-GPC vs Thymulin

Alpha-GPC vs Thymulin

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

Cognitive Enhancement
Alpha-GPC
Immune Support
Thymulin
Summary
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).
Thymulin is a nonapeptide hormone produced exclusively by the thymic epithelium. It requires zinc for biological activity and plays a critical role in T-lymphocyte maturation, differentiation, and immune regulation. Thymulin levels decline dramatically with age, contributing to immunosenescence.
Half-Life
~4–6 hours
~30 minutes active half-life
Admin Route
Oral, SubQ
SubQ
Research
Typical Dose
300–600 mg
20-30 mcg
Frequency
1–2x daily
10 days per month (Khavinson protocol)
Key Benefits
  • 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)
  • Enhances T-cell maturation and differentiation
  • Boosts NK cell cytotoxic activity
  • Reduces inflammatory cytokine production (TNF-α, IL-1)
  • Anti-nociceptive (pain-reducing) properties
  • Restores age-related immune decline
  • Anti-inflammatory via serotonin pathway modulation
Side Effects
  • Headache (paradoxically, from excess acetylcholine at very high doses)
  • Nausea at doses > 1200 mg
  • Dizziness
  • Fatigue at high doses
  • +1 more
  • Injection site reactions
  • Mild fatigue initially as immune system activates
Stacks With