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Tools›Compare›P21 vs VIP

P21 vs VIP

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

Cognitive EnhancementAnti-Aging & Longevity
P21
Immune SupportSleep Optimization
VIP
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.
VIP is a 28-amino acid neuropeptide with profound anti-inflammatory, vasodilatory, and immunomodulatory effects. It plays a critical role in gut motility, circadian rhythm, and immune tolerance. Used therapeutically for CIRS (Chronic Inflammatory Response Syndrome), MCAS, and inflammatory conditions.
Half-Life
Not well characterized; likely short, but neurogenic effects persist long after administration
~2 minutes in plasma (rapidly degraded by peptidases); intranasal delivery may extend local CNS effects
Admin Route
SubQ, Intranasal
Intranasal, SubQ, IV
Research
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Typical Dose
100–500 mcg
50 mcg (4 sprays of 12.5 mcg each)
Frequency
Once daily
4x 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 anti-inflammatory for CIRS and mold illness
  • Improves pulmonary hypertension symptoms
  • Regulates gut motility and IBS symptoms
  • Modulates circadian rhythm and sleep quality
  • Reduces mast cell activation (MCAS)
  • Improves cognitive function in neuroinflammatory conditions
  • Vasodilatory — reduces vascular resistance
Side Effects
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
  • Facial flushing (transient, intranasal)
  • Mild nausea
  • Headache at initiation
  • Hypotension at high doses
  • +1 more
Stacks With
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