AICAR vs P21
Side-by-side comparison of key properties, dosing, and research.
- Summary
- AICAR is a cell-permeable AMP analog that activates AMPK (AMP-activated protein kinase) — the master metabolic switch that triggers fat burning, mitochondrial biogenesis, and adaptations normally only achieved through exercise. It has been called the 'exercise in a pill' compound.
- 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
- ~2–3 hours
- Not well characterized; likely short, but neurogenic effects persist long after administration
- Admin Route
- SubQ, IV
- SubQ, Intranasal
- Research
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- Typical Dose
- 25–50 mg
- 100–500 mcg
- Frequency
- 3–5 times per week
- Once daily
- Key Benefits
- AMPK activation mimics aerobic exercise adaptations
- Increased fat oxidation and endurance
- Mitochondrial biogenesis (PGC-1alpha)
- Improved insulin sensitivity and glucose metabolism
- Anti-inflammatory effects
- Potential cardiac protection during ischemia
- Synergistic with actual exercise training
- Reduces hepatic glucose production
- 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
- Hypoglycemia risk
- Lactic acidosis at high doses (animal data)
- Injection site irritation
- Generally well tolerated in animal studies
- Limited human clinical data
- Injection site reactions
- Potential mild fatigue at initiation
- Stacks With
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