Semax vs PE-22-28
Side-by-side comparison of key properties, dosing, and research.
- Summary
- Semax is a synthetic heptapeptide derived from ACTH developed in Russia. It is a potent nootropic that enhances memory, focus, and provides neuroprotection. Approved in Russia for cognitive disorders, stroke recovery, and traumatic brain injury.
- PE-22-28 is a synthetic analog of spadin derived from sortilin, designed to block TREK-1 potassium channels with rapid-onset antidepressant and neurogenic effects. It shows fast-acting depression relief (within 24 hours) and promotes hippocampal neurogenesis.
- Half-Life
- Minutes (but effects persist for hours via BDNF induction)
- Relatively short; CNS effects may persist due to neurogenic mechanisms
- Admin Route
- Intranasal, SubQ
- SubQ, Intranasal
- Research
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- Typical Dose
- 0.25–1 mg (250–1000 mcg)
- 200–400 mcg
- Frequency
- 1–2 times daily
- Once daily
- Key Benefits
- Enhances memory and learning
- Improves focus and concentration
- Increases mental energy and motivation
- Provides neuroprotection via BDNF and NGF upregulation
- Reduces cognitive decline
- May alleviate ADHD symptoms
- Supports recovery from brain injury and stroke
- Fast-acting — effects within 30–60 minutes
- Approved in Russia for cognitive disorders and stroke recovery
- Rapid-onset antidepressant effects (within 24 hours)
- Promotes hippocampal neurogenesis
- Improves cognitive performance and memory
- Reduces anxiety and depressive behavior
- Novel mechanism — does not act on serotonin/dopamine/GABA receptors directly
- May help treatment-resistant depression
- Neuroprotective effects
- Side Effects
- Headache (rare, often from higher doses)
- Anxiety or overstimulation at high doses
- Sleep disruption if dosed too late
- Irritability (uncommon)
- Generally well tolerated in animal models
- Limited human data available
- Possible mild headache or transient mood changes at initiation
- Injection site reactions (SC)
- Stacks With
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