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ToolsCompareP21 vs Tesofensine

P21 vs Tesofensine

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

Cognitive EnhancementAnti-Aging & Longevity
P21
Fat Loss & Metabolic
Tesofensine
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.
Tesofensine is a triple monoamine reuptake inhibitor (TMRI) that blocks reuptake of serotonin, dopamine, and norepinephrine. Originally developed for Alzheimer's and Parkinson's disease, it was repurposed as a potent weight loss agent after clinical trials demonstrated substantial fat loss via appetite suppression and increased energy expenditure.
Half-Life
Not well characterized; likely short, but neurogenic effects persist long after administration
8-10 days (exceptionally long; accumulates over weeks)
Admin Route
SubQ, Intranasal
Oral
Research
Typical Dose
100–500 mcg
0.25-0.5 mg per day
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
  • Potent appetite suppression via triple monoamine reuptake inhibition
  • Significant weight loss (8-12% body weight in phase II trials at 0.5 mg)
  • Increases basal metabolic rate and energy expenditure
  • Reduces fat mass preferentially over lean mass
  • Potential cognitive benefit via dopaminergic and noradrenergic enhancement
  • Longer half-life than sibutramine allows once-daily dosing
Side Effects
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
  • Elevated heart rate and blood pressure (sympathomimetic)
  • Dry mouth
  • Insomnia and sleep disturbances
  • Nausea
  • +4 more
Stacks With