Dihexa Research Overview (also known as N-hexanoic-Tyr-Ile-(6) aminohexanoic amide)
A synthetic hexapeptide derived from angiotensin IV that promotes synaptogenesis through the HGF/c-Met receptor signaling axis. Developed at Washington State University, Dihexa is studied for its structural neuroplasticity effects and preclinical potency in cognitive and Alzheimer's disease models.
What Is Dihexa?
Dihexa is a synthetic small-molecule peptide analog derived from Angiotensin IV, designed to penetrate the blood-brain barrier and potently activate the HGF (Hepatocyte Growth Factor) / c-Met signaling pathway in the brain. Developed at Washington State University by Joseph Harding et al., it is reported to be approximately 7 orders of magnitude more potent than BDNF at promoting hippocampal synaptogenesis — potentially making it the most powerful synaptogenic compound known.
HGF/c-Met Pathway in Neuroplasticity
HGF acts as a potent neurotrophin in the brain, binding c-Met receptor tyrosine kinase to promote neuron survival, axon sprouting, and synaptogenesis. In the hippocampus, HGF/c-Met signaling is critical for memory consolidation and synaptic plasticity. Dihexa potentiates HGF binding to c-Met with extraordinary potency, dramatically amplifying this neuroprotective and neurogenic signaling cascade.
Cognitive Enhancement and BBB Penetration
In animal studies, Dihexa administration produced dramatic improvements in object recognition memory, spatial memory, and problem-solving tasks — with effects at picomolar concentrations. In aged animals with cognitive deficits, Dihexa restored performance to levels comparable to young animals. Unlike most peptides and proteins, Dihexa's modified structure allows it to cross the blood-brain barrier following systemic administration — oral, intranasal, or subcutaneous — enabling CNS delivery without intrathecal injection.
Quick Reference
| Literature-Reported Dose Range | 8-10mg oral / 0.5mg/kg injectable |
| Literature-Reported Frequency | 1x daily (morning) |
| Literature-Reported Cycle Length | 4-8 weeks on |
| Literature-Reported Washout | 2-4 weeks off |
| Storage | Oral capsules: room temperature. Injectable: requires DMSO to dissolve (Dihexa won't dissolve in water), store DMSO stock solution at 2-8°C. Always use pharmaceutical-grade DMSO. |
| Sites Reported in Studies | SubQ: belly, thigh, upper arm |
| Timing | Morning, with or without food |
Research Indications
Cognitive
Memory Enhancement
Significant improvements in spatial memory, working memory, and memory consolidation demonstrated across multiple animal models.
Learning Acceleration
Enhanced acquisition of new information and skills through increased synaptic plasticity and neurogenesis.
Cognitive Recovery
Restoration of cognitive function in models of impairment, including scopolamine-induced amnesia and age-related decline.
Neuroprotection
Alzheimer's Disease
Reduced amyloid burden, decreased neuroinflammation, and cognitive rescue in APP/PS1 mouse models.
Synaptic Preservation
Protection and restoration of synaptic connections in neurodegenerative disease models.
Anti-inflammatory Effects
Reduction of IL-1β and TNF-α, increased IL-10, and decreased glial activation in brain tissue.
Neuroplasticity
Synaptogenesis
Dramatic increase in dendritic spine formation, up to 3-fold in hippocampal neurons.
BDNF Upregulation
Indirect enhancement of brain-derived neurotrophic factor signaling through HGF/c-Met activation.
Angiogenesis
Promotion of new blood vessel formation in brain tissue through VEGFR2 activation.
Research Protocols
As reported in cited literature and research-community logs (see Research Citations below) — not a personal dosing recommendation.
| Research Application | Dose | Frequency | Route |
|---|
| Research-Based Injectable | 0.5mg/kg | 1x daily | IP/SubQ |
| Cognitive Enhancement | 8-10mg | 1x daily (morning) | Oral |
| Intensive Learning | 10-15mg | 1x daily | Oral |
| Neuroprotection | 5-8mg | Daily or 3x weekly | Oral or SubQ |
| Maintenance | 5mg | Every other day | Oral |
Timing
Recommended administration window: morning, with or without food. Typical onset: 1-3 weeks initial, 4-8 weeks full.
Peptide Interactions
These compounds address different research mechanisms represented in this preset. This is mechanistic complementarity, not evidence of clinical synergy: controlled studies of the exact combination are limited or unavailable, so interpret each exposure and safety signal independently.
Synergistic cognitive and anxiolytic effects when combined, but monitor for neural overstimulation
No known negative interactions - different mechanisms of action
Both are potent synaptogenic compounds. Running both simultaneously in the same cycle creates compounded synaptogenesis load that may cause overstimulation, heightened anxiety, or emotional dysregulation. Use one per cycle, not both concurrently.
Some users stack for cognitive enhancement but limited safety data on combination
Complementary mechanisms - NAD+ supports cellular energy while Dihexa promotes synaptogenesis
Both are potent neurotrophic agents - combining may lead to excessive stimulation
No known interactions - TB-500 focuses on tissue repair while Dihexa targets neural connections
Dihexa is a positive allosteric modulator of the HGF/c-Met pathway. Combining with c-Met–targeted oncology drugs creates unpredictable receptor modulation — the drugs block c-Met while Dihexa activates it. Absolute contraindication.
NSI-189 promotes neurogenesis via a separate mechanism. While not directly contraindicated, combining multiple strong neurogenic compounds in a single cycle is poorly characterized. Use sequentially rather than simultaneously for predictable outcomes.
Reported Research Timeline
01Week 1–2 (reported in cited studies): subtle cognitive changes, possible headaches
02Week 2–4 (reported in cited studies): improved focus and memory formation
03Week 4–8 (reported in cited studies): peak cognitive benefits, enhanced learning
04Post-cycle: Effects may persist for days to weeks
05Common effects: Mental clarity, faster learning
Side effects (reported in cited studies): headaches (most common), anxiety, sleep disruption if taken late
Safety Notes
Included for harm-reduction awareness only, in the event this compound is encountered outside its labeled research use. Inclusion here does not imply RUO Codes endorses, recommends, or instructs human use.
Not FDA approved - research compound only
Theoretical cancer risk via c-Met activation
No long-term human safety data available
Avoid if history of cancer
Not for pregnant/nursing women
May cause overstimulation or anxiety
Requires cycling to prevent tolerance
Anyone with active cancer or a personal/family history of gastric, hepatocellular, or papillary thyroid carcinoma should not use Dihexa — c-Met is the primary driver oncogene in these cancers, and Dihexa’s c-Met activation mechanism carries uncharacterized risk in these individuals.
Headache is the most commonly reported side effect and typically emerges at doses ≥10 mg oral. If persistent, reduce dose rather than increase.
Emotional blunting or anhedonia has been reported by some users during cycles, particularly at higher doses. If experienced, reduce dose or end the cycle — this resolves after stopping.
Do not combine with P21 peptide or NSI-189 in the same cycle. Running multiple potent synaptogenic compounds simultaneously is poorly characterized and may cause anxiety, irritability, or overstimulation.
Titrate extremely conservatively — start at 2–5 mg oral and increase slowly over several days. The compound’s assay potency (10⁷× BDNF in preclinical models) demands a stepwise approach.
Seek Medical Attention If:
Severe or persistent headaches
Increasing anxiety or panic
Significant mood changes or depression
Sleep disturbance beyond 3 days
Any concerning neurological symptoms
Signs of overstimulation or mania
Injection site reactions (if using injectable)
Always consult healthcare provider for guidance
Quality Indicators
Verified Marker
Pharmaceutical Grade
Product from licensed compounding pharmacy with certificate of analysis showing >98% purity.
Verified Marker
Proper Storage Conditions
Shipped and stored according to specifications — room temperature for oral, 2-8°C for DMSO stock solutions.
Acceptable Range
Research Chemical Sources
If sourced as research chemical, ensure third-party testing and proper documentation.
Quality Concern
No Testing Documentation
Avoid products without analytical testing, purity reports, or from unverified sources.
Quality Concern
Suspicious Pricing
Extremely cheap Dihexa likely indicates poor quality or fraudulent product.
Research Citations
- AngIV-Analog Dihexa Rescues Cognitive Impairment and Recovers Memory in the APP/PS1 Mouse via the PI3K/AKT Signaling Pathway
Sun X, Deng Y, Li W, et al., 2021, International Journal of Molecular Sciences - The procognitive and synaptogenic effects of angiotensin IV-derived peptides are dependent on activation of the hepatocyte growth factor/c-met system
Benoist CC, Kawas LH, Zhu M, et al., 2014, Journal of Pharmacology and Experimental Therapeutics - Evaluation of metabolically stabilized angiotensin IV analogs as procognitive/antidementia agents
McCoy AT, Benoist CC, Wright JW, et al., 2013, Journal of Pharmacology and Experimental Therapeutics - The development of small molecule angiotensin IV analogs to treat Alzheimer's and Parkinson's diseases
Wright JW, Kawas LH, Harding JW, 2015, Progress in Neurobiology - Cognitive benefits of angiotensin IV and angiotensin-(1-7): A systematic review of experimental studies
Ho JK, Nation DA, 2018, Neuroscience & Biobehavioral Reviews - Dimeric DOTA-alpha-melanocyte-stimulating hormone analogs: synthesis and in vivo characteristics of radiopeptides with high in vitro activity
Bapst JP, Froidevaux S, Calame M, 2007, J Recept Signal Transduct Res
Research Focus
Cognitive enhancement, Neurogenesis, Synaptogenesis, HGF/c-Met pathway, Memory, Dementia research
Verified Vendors Carrying Dihexa
Frequently Asked Questions
What should researchers watch for with Dihexa?
Included for harm-reduction awareness only, in the event this compound is encountered outside its labeled research use. Inclusion here does not imply RUO Codes endorses, recommends, or instructs human use.
What should researchers expect over time with Dihexa?
Week 1–2 (reported in cited studies): subtle cognitive changes, possible headaches
How is Dihexa typically administered in research?
As reported in cited literature and research-community logs (see Research Citations below) — not a personal dosing recommendation.
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