P21 vs DSIP
Side-by-side comparison of key properties, dosing, and research.
- 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.
- DSIP is an endogenous neuropeptide originally isolated from rabbit cerebrospinal fluid that induces delta-wave (deep) sleep. It also modulates stress response, cortisol regulation, and LH secretion, making it valuable for sleep optimization and stress management.
- Half-Life
- Not well characterized; likely short, but neurogenic effects persist long after administration
- ~30–60 minutes; however downstream sleep effects last 4–6 hours
- Admin Route
- SubQ, Intranasal
- SubQ, IV, Intranasal
- Research
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- Typical Dose
- 100–500 mcg
- 100–400 mcg
- Frequency
- Once daily
- Once nightly
- 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
- Induces and deepens delta-wave (slow-wave) sleep
- Reduces cortisol and normalizes HPA axis
- Improves sleep quality in insomnia patients
- Anti-stress and anxiolytic effects
- May improve opiate/alcohol withdrawal symptoms
- Analgesic properties through opioid modulation
- Antioxidant and neuroprotective effects
- Side Effects
- Generally well tolerated in animal studies
- Limited human clinical data
- Injection site reactions
- Potential mild fatigue at initiation
- Generally well tolerated
- Mild grogginess next morning at higher doses
- Rare: hypotension
- Potential for altered dream patterns
- Stacks With
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