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ToolsCompareP21 vs Liraglutide

P21 vs Liraglutide

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

Cognitive EnhancementAnti-Aging & Longevity
P21
GLP-1 / Weight Loss AgonistsFat Loss & Metabolic
Liraglutide
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.
Liraglutide is a long-acting GLP-1 receptor agonist approved for type 2 diabetes (Victoza) and chronic weight management (Saxenda). It reduces appetite, slows gastric emptying, improves insulin secretion, and promotes weight loss of 5–10% in clinical trials.
Half-Life
Not well characterized; likely short, but neurogenic effects persist long after administration
~13 hours (once-daily dosing)
Admin Route
SubQ, Intranasal
SubQ
Research
Typical Dose
100–500 mcg
Start 0.6 mg, titrate to 3 mg
Frequency
Once daily
Once 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
  • Promotes weight loss (5–10% average)
  • Reduces appetite and caloric intake
  • Improves blood glucose control (HbA1c reduction)
  • Reduces cardiovascular events in T2DM (LEADER trial)
  • Slows gastric emptying
  • FDA-approved for T2DM and chronic weight management
  • Cardioprotective effects shown in clinical trials
  • May improve fatty liver (NAFLD/NASH)
Side Effects
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
  • Nausea (very common, especially initially)
  • Vomiting
  • Diarrhea or constipation
  • Decreased appetite
  • +5 more
Stacks With