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ToolsCompareP21 vs NAD+

P21 vs NAD+

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

Cognitive EnhancementAnti-Aging & Longevity
P21
Anti-Aging & Longevity
NAD+
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.
NAD+ (Nicotinamide Adenine Dinucleotide) is a coenzyme found in all living cells that declines dramatically with age. It is critical for energy metabolism, DNA repair, and sirtuin activation. IV and subcutaneous NAD+ supplementation is used in anti-aging protocols and addiction recovery programs.
Half-Life
Not well characterized; likely short, but neurogenic effects persist long after administration
Varies by route; IV provides direct cellular delivery
Admin Route
SubQ, Intranasal
IV, SubQ, Oral
Research
Typical Dose
100–500 mcg
500–1000 mg
Frequency
Once daily
Daily for 4–10 days (loading), then monthly maintenance
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
  • Restored cellular energy production (ATP)
  • Sirtuin activation for longevity and metabolic regulation
  • Enhanced DNA repair capacity
  • Improved mitochondrial function and biogenesis
  • Cognitive clarity and mental energy
  • Reduced inflammation
  • Addiction withdrawal support (opioids, alcohol, benzodiazepines)
  • Improved sleep quality
  • Enhanced athletic endurance
Side Effects
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
  • Flushing and warmth during IV infusion
  • Nausea during rapid IV administration
  • Chest tightness (from rapid infusion — slow the rate)
  • Injection site irritation (subcutaneous)
  • +1 more
Stacks With