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ToolsCompareP21 vs Noopept

P21 vs Noopept

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

Cognitive EnhancementAnti-Aging & Longevity
P21
Cognitive Enhancement
Noopept
Summary
P21 is a synthetic peptide derived from CNTF (ciliary neurotrophic factor) that promotes hippocampal neurogenesis, enhances memory and spatial learning, and may reduce amyloid-beta pathology. It is used as a neurogenic and cognitive enhancer with potential anti-Alzheimer's applications.
Noopept is a potent dipeptide-derived nootropic from Russia, structurally related to piracetam but estimated to be 1,000 times more potent by mass. It enhances memory consolidation, learning, and recall while providing neuroprotection via BDNF and NGF upregulation.
Half-Life
Not well characterized; likely short, but neurogenic effects persist long after administration
~5–10 minutes but metabolite (CPG) effects last hours
Admin Route
SubQ, Intranasal
Oral, Sublingual, Intranasal
Research
Typical Dose
100–500 mcg
10–30 mg
Frequency
Once daily
1–2x daily
Key Benefits
  • Promotes hippocampal neurogenesis
  • Enhances spatial memory and learning
  • Increases BDNF expression
  • Reduces amyloid-beta plaque formation (animal models)
  • Anti-tau pathology potential
  • Cognitive enhancement without stimulant effects
  • Potential therapeutic for Alzheimer's and cognitive aging
  • Enhances memory formation and recall
  • Improves learning speed and cognitive processing
  • Neuroprotective via BDNF/NGF upregulation
  • Anxiolytic at low-to-moderate doses
  • Improves verbal fluency and information processing
  • Antioxidant (reduces oxidative damage in neurons)
  • May improve cognitive symptoms of mild cognitive impairment
Side Effects
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
  • Headaches (choline depletion — pair with choline source)
  • Irritability or anxiety at high doses
  • Overstimulation
  • Rare: brain fog with chronic use
  • +1 more
Stacks With