Semax vs Dihexa
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.
- Dihexa is a potent experimental oligopeptide derived from angiotensin IV that dramatically enhances synaptogenesis. Preclinical research shows cognitive enhancement orders of magnitude more potent than BDNF — it is considered one of the most powerful nootropic compounds in research, but has very limited human safety data.
- Half-Life
- Minutes (but effects persist for hours via BDNF induction)
- Unknown (limited pharmacokinetic data)
- Admin Route
- Intranasal, SubQ
- Oral, SubQ, Topical
- Research
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- Typical Dose
- 0.25–1 mg (250–1000 mcg)
- 5–10 mg
- Frequency
- 1–2 times daily
- 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
- Dramatically increases synapse formation (potentially 10 million× more potent than BDNF in animal models)
- Enhances memory and learning
- May reverse cognitive decline
- Improves neuroplasticity and executive function
- Long-lasting cognitive benefits from short courses
- Potential therapeutic agent for Alzheimer's
- Side Effects
- Headache (rare, often from higher doses)
- Anxiety or overstimulation at high doses
- Sleep disruption if dosed too late
- Irritability (uncommon)
- Headache
- Irritability
- Brain fog during washout period
- Unknown long-term effects (insufficient data)
- Stacks With
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