Dihexa Evidence Guide
Evidence for Dihexa is too preliminary to support a research protocol with confidence. Human data is essentially absent - research is confined to rodent models of cognitive decline. Of the Cognitive & Nootropic compounds, cerebrolysin or semax have at minimum regional human evidence as better-characterized starting points.
Our Take
Evidence for Dihexa is too preliminary to support a research protocol with confidence. Human data is essentially absent - research is confined to rodent models of cognitive decline. Of the Cognitive & Nootropic compounds, cerebrolysin or semax have at minimum regional human evidence as better-characterized starting points.
- Best for
- Preclinical cognitive enhancement research, HGF/Met pathway, synaptogenesis models
- Evidence grade
- Level D
- Confidence
- Low
- Starting point
- No human protocol established - evidence is preclinical only
Benefits and Evidence
- Memory Enhancement: Level D, mostly non-human evidence - McCoy et al. (2013, J Pharmacol Exp Ther) showed Dihexa at picomolar doses (10^-13 M) reversed scopolamine-induced amnesia in rats via Morris water maze and novel object recognition; active at ~10^7-fold lower concentrations than BDNF for HGF/c-Met-dependent synaptogenesis in hippocampal neurons.
- Synaptogenesis: Level D, mostly non-human evidence - In vitro and animal studies demonstrate significant promotion of new synaptic connections. May be relevant for neurodegenerative disease treatment.
Side Effects and Warnings
- No human safety data available
- Theoretical risk of excessive cell growth (HGF pathway)
- Unknown long-term effects
- Quality control concerns with available research material
- EXTREMELY EARLY STAGE - animal data only
- No human clinical trials conducted
- HGF/c-Met pathway involved in cancer cell growth and metastasis
- Serious theoretical safety concerns
Research Dosage References
- <strong>Oral</strong> - 5-20 mg - Once daily - Research dosing extrapolated from animal studies. No established human dosing protocol. Orally bioavailable.
- <strong>Subcutaneous</strong> - 1-5 mg - Once daily - Alternative route used in some research contexts. Higher bioavailability than oral.
Mechanism of Action
Dihexa works through the HGF/c-Met pathway: 1. HGF/c-Met activation: Stabilizes hepatocyte growth factor, enhancing its binding to the c-Met receptor. 2. Synaptogenesis: Promotes formation of new synaptic connections between neurons, enhancing neural network connectivity. 3. Dendritic spine growth: Stimulates growth of dendritic spines, the key structures for synaptic transmission. 4. Neurogenesis: May promote generation of new neurons in hippocampal regions critical for memory. 5. Blood-brain barrier penetration: Small molecular size allows oral bioavailability and CNS penetration.
Legal Status
Dihexa is a research chemical with no regulatory approval for any use. Not a controlled substance but not approved for human consumption. Available through research chemical suppliers with varying quality. Extreme caution advised.
Primary Sources
- Dihexa: a nootropic hexapeptide analog of angiotensin IV. J Pharmacol Exp Ther, 2013.
- Hepatocyte growth factor/c-Met signaling and Dihexa. Hippocampus, 2014.