Cognitive
Dihexa
Longevity
2
Amino acids
Molecular weight
Peptide
Type
Dihexa (PNB-0408) is a synthetic oligopeptide derived from angiotensin IV, developed at Washington State University. It binds hepatocyte growth factor (HGF) and potentiates its signaling at the c-Met receptor, driving synaptogenesis at a potency reported to be seven orders of magnitude greater than BDNF in vitro. It is used in preclinical research focused on neurodegenerative disease, traumatic brain injury, and cognitive optimization.
Top researched benefits
Overview of Dihexa
Dihexa binds with high affinity to hepatocyte growth factor (HGF) and potentiates its activity at the c-Met receptor on neuronal membranes, activating downstream PI3K/Akt and MAPK/ERK signaling cascades that upregulate synaptic proteins, promote dendritic growth, and drive new synapse formation in hippocampal neurons.
cognitive
- Improvements in spatial, working, and consolidation demonstrated across animal models.
- Enhanced acquisition through increased synaptic plasticity.
- Restoration in impairment models including scopolamine-induced amnesia.
neuroprotection
- Reduced amyloid burden in Alzheimer's models.
- Decreased neuroinflammation and glial activation.
- Protection of synapses in neurodegeneration models.
neuroplasticity
- 3-fold increase in dendritic spine formation demonstrated.
- Increases brain-derived neurotrophic factor expression.
- Promotes new blood vessel formation in brain.
Typical Dose
10–15mg per dose
Frequency
once daily
Cycle Duration
4–6 weeks on, with extended off period due to long accumulation half-life
Storage
Lyophilized: store below -18°C; stable at room temperature up to 3 weeks. Reconstituted in bacteriostatic water: store at 2–8°C and use within 2–7 days, or freeze below -18°C for longer term; avoid repeated freeze-thaw cycles.
Chemical Makeup
Key benefits
Drives synaptogenesis in hippocampal neurons at potency reported to be 10 million times greater than BDNF in neurotrophic assays
Restored spatial learning and memory in APP/PS1 Alzheimer's mouse model, outperforming donepezil (Aricept) in Morris water maze tests
Reversed motor deficits in Parkinson's disease animal models following oral or subcutaneous administration
Increases dendritic spine density by 40–60% and upregulates synaptophysin (SYP) protein expression in preclinical neurodegeneration models
Community interest
This peptide is still gaining traction in the community.
HGF/c-Met Agonist | Cognitive Enhancement & Neuroregeneration
This overview is informational and based on aggregated descriptions from studies and user reports.
Was it helpful?YesNoDihexa Molecular Information
View the scientifc details of Dihexa.
2
Amino Acids
Dihexa
Tyr
Tyr
Position 1
Ile
Ile
Position 2
Molecular Weight
504.67DaChain Length
2Amino AcidsType
PeptideDihexa Protocols
Subcutaneous injection delivers Dihexa directly into systemic circulation, bypassing first-pass hepatic metabolism and the variability of gastrointestinal absorption — though Dihexa is unusual among peptides in being orally bioavailable itself. Because Dihexa carries an approximately 12-day half-life, injected doses accumulate significantly over a multi-week protocol, so conservative starting doses are critical to avoid overshooting therapeutic targets.
| Goal | Dosage | Frequency | Route |
|---|---|---|---|
| Promote initial synaptogenesis and improve learning capacity with a conservative dose that accounts for Dihexa's long half-life and cumulative build-up | 2 | 1 day range | SubQ |
| Support ongoing synaptic density maintenance and neuroprotection against age-related cognitive decline at a mid-range therapeutic dose | 4 | 1 day range | SubQ |
| Maximize synaptogenic and memory-consolidation effects in experienced users after tolerance has been established at lower doses | 7 | 1 day range | SubQ |
| Target recovery of memory deficits and structural neural repair in the context of age-related neurodegeneration or traumatic brain injury sequelae | 5 | 1 day range | SubQ |
| Reduce receptor desensitization risk and allow neural integration of synaptogenic changes by cycling Dihexa with mandatory off periods | 3 | 1 day range | SubQ |
Reconstitution Instructions
Materials needed:
Steps to reconstitute
- Remove the lyophilized Dihexa vial from the freezer and allow it to reach room temperature for 10–15 minutes before reconstituting.
- Draw the required volume of bacteriostatic water into an insulin syringe — for a 10 mg vial, use 1 mL of BAC water to achieve a 10 mg/mL concentration; for a 15 mg vial, use 1.5 mL to achieve the same concentration.
- Insert the needle through the rubber stopper of the Dihexa vial at a slight angle and inject the BAC water slowly down the inside wall of the vial — never directly onto the lyophilized powder cake.
- Remove the syringe and gently swirl the vial in slow circular motions until the powder is fully dissolved. Do not shake or vortex, as mechanical shearing destroys peptide integrity and c-Met binding affinity.
- Inspect the solution — it should be clear and free of particulate matter. Discard if cloudy or discolored.
- Store the reconstituted vial refrigerated at 2–8°C, protected from light, and use within 14–28 days. Freeze unused aliquots at -20°C to extend stability, minimizing freeze-thaw cycles.
- At time of injection, draw the desired dose into a clean insulin syringe. Remove air bubbles by tapping the syringe and gently pressing the plunger until a drop appears at the needle tip.
- Clean the injection site (abdomen, thigh, or upper arm) with an alcohol swab and allow to air dry completely before injecting.
- Pinch a fold of skin, insert the needle at a 45-degree angle subcutaneously, aspirate briefly, then inject slowly and steadily.
- Remove the needle, apply gentle pressure with a clean swab, and log the injection site. Rotate sites each administration to prevent lipodystrophy.
Dihexa Cycle
The Dihexa Cycle section explains how long a typical cycle lasts and what to expect during each phase. Over time, your body can become less responsive with continuous use.
Taking breaks between cycles may help maintain effectiveness and support better overall results.
- Week 1-2
- Subtle cognitive shifts; possible headaches during adaptation
- Week 2-4
- Improved focus and memory formation
- Week 4-8
- Peak cognitive benefits and enhanced learning
- Week 0-0
- Effects may persist for days to weeks after discontinuation
Dosing tools
Dihexa Peptide Dosage Calculator
Calculate peptide doses with our visual syringe guide.
mg
Enter the total amount of peptide in the vial in milligrams (as stated on the label).
The dose you want to inject per administration, in mcg or mg.
1,000 mcg = 1 mg
1 mL
2 mL
3 mL
5 mL
Custom
Volume of bacteriostatic water you add to reconstitute the powder. Use BAC water for preservation.
Injection Results
Based on your vial and dilution inputs.
Dihexa
SINGLE COMPOUNDVolume per injection
0.05
mL
Concentration
10.00
mg/mL
Doses per vial
20
doses
Total injections per vial
20 injections
How it works
Based on a 10 mg Dihexa vial diluted with 1 mL of bacteriostatic water, each 500 mcg injection equals 0.05 mL.
1mL / 100 units
5 units
0.050 mL
Reference Guide
Dosing Cycle
- Peptide
- Dihexa
- Dosing
- 10–15mg per dose
- Dosing Frequency
- once daily
- Cycle Duration
- 4–6 weeks on, with extended off period due to long accumulation half-life
- Storage
- Lyophilized: store below -18°C; stable at room temperature up to 3 weeks. Reconstituted in bacteriostatic water: store at 2–8°C and use within 2–7 days, or freeze below -18°C for longer term; avoid repeated freeze-thaw cycles.
Note: Triple agonist; microdose for fewer side effects
Reconstitution Tips
- Use bacteriostatic water (BAC) — contains 0.9% benzyl alcohol for preservation
- Inject water slowly — aim down the vial wall, not directly onto powder
- Never shake — gently swirl or roll the vial until dissolved
- Store properly — refrigerate at 2-8°C after reconstitution
- Use within 28 days — most reconstituted peptides remain stable for about 4 weeks
- Keep sterile — always clean vial tops with alcohol before drawing
Peptide Interactions
Research suggestions of Dihexa interactions with other common peptides and substances.
Cognitive
cer
Longevity
Cerebrolysin
MONITOR
Both potently neuroactive; may cause overstimulation.
Cognitive
sel
Longevity
Selank
COMPATIBLE
Synergistic effects; watch for neural overstimulation.
Cognitive
sema
Longevity
Semax
COMPATIBLE
Enhanced cognitive benefits; monitor for overstimulation.
Side effects
Avoid: Do not take Dihexa with P21.
Monitor: Be careful when combining Dihexa with Cerebrolysin.
Contraindications
Not FDA approved - research compound only
Theoretical cancer risk via c-Met activation
Cancer history (avoid due to c-Met pathway)
Pregnancy or breastfeeding
No long-term human safety data
Stop signs
Severe or persistent headaches
Increasing anxiety or panic attacks
Significant mood changes or depression
Sleep disturbance beyond 3 days
Concerning neurological symptoms
Signs of overstimulation or mania
Injection site reactions (if injectable)
Bad signs
Comments
0.0
0 reviews
5
4
3
2
1
No comments yet
Be the first to share your experience. Your review helps others make more informed decisions.
Frequently asked questions
What is a peptide dosage calculator?
A peptide dosage calculator is a free tool that converts your vial size, bacteriostatic water volume, and target dose into an exact syringe draw volume. Instead of doing the reconstitution math by hand, you enter three inputs and instantly get the concentration of your solution and how many milliliters or syringeunits to draw. This calculator works for single peptide compounds and multi-peptide blends.
How do I calculate peptide dosage from a vial?
To calculate your peptide dose, divide the total peptide content of your vial in micrograms by the volume of bacteriostatic water you added in milliliters. This gives you your solution concentration in mcg/mL. Then divide your target dose by that concentration to get your draw volume. For example, a 5mg (5,000 mcg) vial reconstituted with 2mL of BAC water gives a concentration of 2,500 mcg/mL. A 250 mcg dose would require drawing 0.1mL. This calculator automates all of those steps instantly.
How much Bacteriostatic water should I add to a peptide vial?
Most people add 2mL to 3mL of bacteriostatic water per vial, but the right amount depends on the dose you want to draw and the syringe size you are using. Adding 1mL to a 5mg vial gives you a concentration of 5,000 mcg/mL, making each dose very small in volume. Adding 2mL gives you 2,500 mcg/mL, which is easier to measure on a standard insulin syringe. A general guideline is to choose a volume that puts your typical dose somewhere between 10 and 30 units on a U-100 syringe. Use the calculator above to test different water volumes and find what works for your dose.
How are peptides different from proteins?
Both are made of amino acids, but peptides are much smaller than proteins. Because of their tiny size, peptides can act like tiny messengers in the body, sending specific signals to your cells to tell them exactly what to do.
DihexaResearch References
Dihexa is a preclinical compound
Dihexa
Dihexa is a preclinical compound
Injectable Route Efficacy Study
Intraperitoneal injection at 0.5mg/kg/day completely reversed scopolamine-induced cognitive deficits (p<0.001), with performance indistinguishable from healthy controls.
2013
APP/PS1 Alzheimer's Model Study
Dihexa restored spatial learning and memory in Morris water maze tests, increased neuronal cells and synaptophysin expression, reduced neuroinflammation.
2021
Synaptogenic Potency Study
Demonstrated to be 10 million times more effective than BDNF at promoting synapse formation through HGF/c-Met receptor activation.
2014
Calculate peptide dosages
Learning how to calculate a peptide dose? Use our beginner-friendly peptide dosage, blend, and accumulation calculators. Enter vial size, reconstitution volume, and target dose to get exact draw volumes instantly. No guesswork, just clear guidance that helps prevent common mistakes.
