Liraglutide vs P21
Side-by-side comparison of key properties, dosing, and research.
GLP-1 / Weight Loss AgonistsFat Loss & Metabolic
LiraglutideCognitive EnhancementAnti-Aging & Longevity
P21- Summary
- 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.
- 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.
- Half-Life
- ~13 hours (once-daily dosing)
- Not well characterized; likely short, but neurogenic effects persist long after administration
- Admin Route
- SubQ
- SubQ, Intranasal
- Research
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- Typical Dose
- Start 0.6 mg, titrate to 3 mg
- 100–500 mcg
- Frequency
- Once daily
- Once daily
- Key Benefits
- 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)
- 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
- Side Effects
- Nausea (very common, especially initially)
- Vomiting
- Diarrhea or constipation
- Decreased appetite
- +5 more
- Generally well tolerated in animal studies
- Limited human clinical data
- Injection site reactions
- Potential mild fatigue at initiation
- Stacks With
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