Dihexa Dosage Guide

Evidence-based protocols for the HGF/c-Met synaptogenic peptidomimetic — animal study evidence, oncological safety concerns, community dosing protocols, stacking, cycling, and what the research actually shows.

Compiled by PeptideWiki Editorial Team·Last reviewed February 24, 2026

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Research Peptides

Dihexa

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What Is Dihexa?

Dihexa (N-hexanoic-Tyr-Ile-(6) aminohexanoic amide) is a synthetic peptidomimetic — a modified hexapeptide analog derived from angiotensin IV. It was developed by Dr. Joseph Harding and colleagues at Washington State University as a cognitive-enhancing research compound. Dihexa is not a traditional peptide but rather a small-molecule peptidomimetic designed to cross the blood-brain barrier and activate the hepatocyte growth factor (HGF) signaling pathway.

Dihexa's proposed mechanism centers on the HGF/c-Met pathway. It binds to the hepatocyte growth factor receptor (c-Met) and promotes dendritic spine formation, synaptogenesis, and neural connectivity. In a widely cited in vitro study (McCoy et al., 2013), Dihexa was reported to be approximately 10 million times more potent than brain-derived neurotrophic factor (BDNF) at promoting new synapse formation in cell culture. This statistic — while accurate in context — is frequently misunderstood and misrepresented.

Critical context: The “10 million times more potent than BDNF” claim describes in vitro synaptogenic activity in a single cell culture assay. It does NOT mean Dihexa is 10 million times more effective as a nootropic in humans. Molecular potency at a cellular target does not translate linearly to cognitive enhancement in living organisms. This distinction matters enormously.

Dihexa has no published human clinical trials. All efficacy data comes from animal studies (primarily rats) and in vitro experiments. This makes it one of the least evidence-supported compounds in the research peptide space. Users should understand they are working with a very early-stage research compound with no established human safety or efficacy profile.

Use our Peptide Dosage to calculate your exact dose based on vial size and concentration.

Dosing information in this guide is derived from animal studies and community protocols — not from approved pharmaceutical labeling or human clinical trials.

Key Characteristics:

Peptidomimetic — a modified hexapeptide analog of angiotensin IV, not a traditional peptide; designed to cross the blood-brain barrier
HGF/c-Met activator — binds hepatocyte growth factor receptor (c-Met) to promote dendritic spine formation and synaptogenesis
Dosed in milligrams — typical doses are 10–20 mg — NOT micrograms. This is significantly more by weight than most research peptides
No human clinical trials — all data from animal studies (rats) and in vitro experiments. No human pharmacokinetic, safety, or efficacy data exists
HGF/c-Met oncological concern — the HGF/c-Met pathway is implicated in tumor growth, metastasis, and angiogenesis. This is a legitimate and significant safety consideration
Administration — subcutaneous injection (primary); some protocols describe intranasal use; oral bioavailability appears low

For a complete overview of its mechanism and research, see our full Dihexa profile. New to peptides? Start with the Beginner's Guide to Peptides.

Evidence Limitations — Read This First

This section is unusually important. Dihexa has one of the weakest evidence bases of any peptide in this guide series. Before reading dosing protocols, you need to understand what is and is not known about this compound.

What the Research Shows

In vitro: Dihexa promotes synaptogenesis and dendritic spine formation in neuronal cell cultures at picomolar concentrations, vastly more potent than BDNF in this specific assay (McCoy et al., 2013)
Animal studies: In rats with scopolamine-induced cognitive impairment, Dihexa restored performance on spatial learning tasks (Morris water maze, novel object recognition) when administered at doses of approximately 0.1–2 mg/kg (Benoist et al., 2014; McCoy et al., 2013)
Mechanism: Dihexa facilitates HGF dimerization and c-Met receptor activation, which triggers downstream pro-survival and synaptogenic signaling cascades including PI3K/Akt and MAPK/ERK pathways (Benoist et al., 2014)

What Is NOT Known

Human pharmacokinetics: No data on absorption, distribution, metabolism, or elimination in humans
Human efficacy: No controlled studies measuring cognitive outcomes in humans
Human safety: No short-term or long-term safety data in humans
Dose-response in humans: No data establishing optimal human dosing
Half-life in humans: Not precisely characterized; animal data suggests moderate duration of action
Oncological risk: No studies measuring cancer incidence or biomarkers with Dihexa use in any species over extended periods

Where Community Dosing Comes From

All human dosing protocols for Dihexa are extrapolated from rat study doses using standard allometric scaling (body surface area conversion), combined with anecdotal community experience. There is no human dose-finding study, no pharmacokinetic modeling, and no dose-response curve in humans. This is a fundamentally different evidence base than peptides like Ipamorelin or Sermorelin, which have been tested in human clinical trials.

Evidence grade: Very limited. Dihexa has promising preclinical data but zero human clinical evidence. All dosing protocols in this guide should be understood as community-derived extrapolations from animal data — not clinically validated recommendations. Proceed with appropriate caution and medical consultation.

How Dihexa Dosage Is Determined

Unlike peptides with human clinical data, Dihexa dosing is derived entirely from allometric scaling of animal studies and community trial-and-error. Understanding the basis for these dosing extrapolations helps contextualize the uncertainty involved.

Animal Study Doses

In the key studies from Harding's lab, rats were administered Dihexa at doses ranging from 0.1 to 2 mg/kg, typically via subcutaneous or intraperitoneal injection. Cognitive restoration in impaired rats was observed across this dose range. Using standard FDA allometric scaling (dividing rat dose by approximately 6.2 for human equivalent dose based on body surface area), a 2 mg/kg rat dose translates to roughly 0.32 mg/kg in humans — approximately 19–26 mg for a 60–80 kg adult.

Community-Derived Protocols

The research community has converged on dosing ranges of 5–30 mg daily via subcutaneous injection, with 10–20 mg being the most commonly reported dose. This range roughly aligns with the allometric scaling calculations above. Users typically start at the lower end (5–10 mg) and titrate upward based on subjective response.

Why Milligrams Instead of Micrograms

Most research peptides are active at microgram (mcg) doses — hundreds to thousands of times less than a milligram. Dihexa requires milligram dosing because it is a small peptidomimetic with different receptor binding kinetics, metabolic clearance, and bioavailability than larger peptides. The absolute amount of compound needed for biological activity is much higher. This is not unusual for peptidomimetics and small molecules, but it catches users off guard who are accustomed to microgram-dosed peptides.

Critical unit warning: Dihexa doses are in MILLIGRAMS (mg), not micrograms (mcg). A standard dose is 10–20 mg. If you are accustomed to dosing peptides like BPC-157 (250 mcg) or Ipamorelin (200 mcg), understand that Dihexa dosing is on a completely different scale. Double-check your units before every injection.

Standard Dihexa Dosage Ranges

Dihexa is administered by subcutaneous injection, typically once daily. There is no clinically validated dosing protocol — the ranges below are derived from allometric scaling of animal studies and community experience. Start at the low end and titrate based on individual response.

Dosage by Experience Level

Level	Dose per Injection	Frequency	Notes
Conservative Start	5–10 mg SubQ	Once daily	Recommended starting point; assess tolerance and subjective response before increasing
Standard Nootropic	10–20 mg SubQ	Once daily	Most commonly reported dose range in community protocols
Higher Protocol	20–30 mg SubQ	Once daily	Upper range; no evidence that higher doses produce proportionally better cognitive outcomes; increased safety uncertainty

Administration Routes

Route	Bioavailability	Community Use	Notes
Subcutaneous	Not characterized (assumed moderate)	Primary route	Most commonly used; all dosing protocols are based on SubQ administration
Intranasal	Unknown (likely lower)	Some protocols	Doses not well-established; may offer more direct CNS delivery but bioavailability is uncertain
Oral	Low	Rarely used	Poor oral bioavailability; not recommended as primary route

Injection Timing

Once daily: Most protocols use a single daily injection, typically in the morning
Fasting status: Unlike GH-releasing peptides, there is no established requirement for fasting with Dihexa. However, some users prefer morning administration on an empty stomach as a general practice
Consistency: Administer at roughly the same time each day to maintain consistent exposure

No dose-response ceiling established: Unlike Hexarelin (which has a well-documented 200 mcg ceiling), there is no clinical data establishing a Dihexa dose-response ceiling in humans. The community consensus to stay at or below 20–30 mg daily is based on allometric scaling and the precautionary principle — not on demonstrated diminishing returns.

Nootropic Peptide Comparison

Dihexa is one of several research peptides used for cognitive enhancement. They differ significantly in mechanism, evidence base, safety profile, and regulatory status. This comparison helps contextualize where Dihexa fits relative to better-established nootropic peptides.

Parameter	Dihexa	Semax	Selank
Mechanism	HGF/c-Met synaptogenesis	BDNF/NGF modulation, monoamines	GABA modulation, anxiolysis, BDNF
Human Clinical Data	None	Yes (approved in Russia)	Yes (approved in Russia)
Primary Route	Subcutaneous	Intranasal	Intranasal
Typical Dose	10–20 mg (milligrams)	200–600 mcg (micrograms)	250–500 mcg (micrograms)
Oncological Concern	Significant (HGF/c-Met)	Low	Low
Evidence Strength	Very limited (animal only)	Moderate (human + animal)	Moderate (human + animal)
Primary Benefit	Synaptogenesis (theoretical)	Focus, neuroprotection	Anxiolysis, cognitive clarity
Safety Profile	Unknown in humans	Well-tolerated	Well-tolerated

Key takeaway: Dihexa has the most novel mechanism and the highest theoretical potency for synaptogenesis, but it also carries the most uncertainty and the highest safety concern. Semax and Selank have significantly more human data, established safety profiles, and pharmaceutical approval (in Russia). For users prioritizing evidence-based decision-making, Semax and Selank represent lower-risk nootropic options.

Calculate Your Dihexa Dose

Dihexa is supplied as a lyophilized (freeze-dried) powder, typically in vials of 10 mg, 20 mg, or 50 mg. You reconstitute it with bacteriostatic water, then draw your dose using an insulin syringe. Because Dihexa is dosed in milligrams, the concentration per mL is much higher than most peptides — so reconstitution volumes matter greatly.

Worked Example:

Vial size: 50 mg of Dihexa
Bacteriostatic water added: 2.5 mL
Concentration: 50 mg ÷ 2.5 mL = 20 mg per mL
Target dose: 10 mg
Volume to draw: 10 ÷ 20 = 0.5 mL = 50 units on an insulin syringe

Quick Reference — 50 mg Vial

Bac Water Added	Concentration	10 mg Dose	20 mg Dose
1 mL	50 mg/mL	20 units (0.2 mL)	40 units (0.4 mL)
2 mL	25 mg/mL	40 units (0.4 mL)	80 units (0.8 mL)
2.5 mL	20 mg/mL	50 units (0.5 mL)	100 units (1.0 mL)
5 mL	10 mg/mL	100 units (1.0 mL)	N/A (exceeds syringe)

Reconstitution tip: Because Dihexa doses are large (milligrams), using too much bacteriostatic water creates very dilute solutions that require drawing large volumes. Conversely, too little water creates very concentrated solutions where small measurement errors cause significant dosing inaccuracies. A concentration of 20–25 mg/mL (2–2.5 mL of water in a 50 mg vial) provides a good balance for accurate measurement.

Skip the Math — Use Our

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Dihexa Dosage by Goal

Dihexa is used primarily for cognitive enhancement goals, though the lack of human data means all protocols are speculative. The following goal-based protocols reflect community practice, not clinical recommendations.

General Cognitive Enhancement

The most common use case — users seeking improvements in memory, learning, mental clarity, and overall cognitive function. This protocol starts conservatively to assess individual response.

Dose: 10–20 mg SubQ daily
Frequency: Once daily, morning
Cycle: 2–4 weeks on, 2–4 weeks off
Assessment: Track subjective cognitive performance (memory, focus, verbal fluency) in a journal to evaluate response

Neuroprotection & Recovery Support

Some users explore Dihexa for neuroprotective purposes — supporting neural recovery following injury, illness, or cognitive decline. The theoretical basis is HGF/c-Met-mediated neurotrophic support and synaptogenesis. Evidence for this use case comes exclusively from animal models.

Dose: 10–20 mg SubQ daily
Frequency: Once daily
Cycle: 3–4 weeks on, 4 weeks off
Note: Synaptogenesis is a slow process — structural neural changes require weeks to develop. Do not expect overnight results.

Conservative / First-Time Protocol

For users trying Dihexa for the first time. Starts at the lowest commonly reported dose to assess tolerance and individual response before considering dose escalation. The cautious approach is warranted given the absence of human safety data.

Dose: 5–10 mg SubQ daily
Frequency: Once daily
Cycle: 2 weeks on, 2–4 weeks off
Titration: If well-tolerated and no adverse effects after 1 week, consider increasing to 10–15 mg daily for the remainder of the cycle

No clinical validation for any goal. All goal-based protocols above are extrapolated from animal studies and community reports. There is no clinical evidence that any specific Dihexa dose produces a specific cognitive outcome in humans. Manage expectations accordingly and prioritize safety by keeping cycles short and doses moderate.

Cognitive tracking is essential. Because Dihexa's effects are entirely subjective and unvalidated in humans, keeping a structured cognitive journal is the only way to assess whether it is producing meaningful results for you. Track memory, focus, verbal fluency, mood, sleep, and any side effects daily throughout the cycle.

Cycling Protocols

Cycling Dihexa is strongly recommended — not because desensitization has been documented (as with GHRPs), but because of the HGF/c-Met oncological concern. Chronic activation of the HGF/c-Met pathway without breaks is imprudent given the known role of this pathway in cancer biology. No established clinical cycling protocol exists; the recommendations below are based on the precautionary principle and community consensus.

Cycling is a safety precaution, not a performance strategy. With Dihexa, the reason for cycling is to limit cumulative exposure to chronic HGF/c-Met activation. This is fundamentally different from cycling GHRPs (which is done to prevent receptor desensitization). The shorter the cycle, the lower the cumulative risk.

Cycling Protocols

Protocol	On-Cycle	Off-Cycle	Notes
Conservative	2 weeks	4 weeks off	Lowest cumulative exposure; recommended for first-time users and those prioritizing safety
Standard	3–4 weeks	3–4 weeks off	Most commonly reported community protocol; balance of exposure and potential benefit
Extended	4 weeks	4–8 weeks off	Maximum on-cycle duration recommended; longer off-periods provide additional safety margin

Cycling Rationale

HGF/c-Met pathway risk: Continuous activation of a pro-growth, pro-angiogenic signaling pathway without breaks increases theoretical oncological risk. Cycling limits cumulative exposure.
Unknown cumulative effects: Without long-term safety data, periodic breaks allow the body to clear the compound and return to baseline HGF/c-Met signaling.
Synaptogenic timeline: Neural structural changes (new synapses, dendritic spine growth) are not rapidly reversible. Benefits from an on-cycle may persist into the off-period as newly formed neural connections stabilize.
Assessment windows: Off-cycle periods allow you to evaluate whether cognitive improvements persist without the compound, which helps distinguish real structural neural changes from acute pharmacological effects.

During off-cycles: You can use alternative nootropic peptides with different mechanisms, such as Semax or Selank, which do not activate the HGF/c-Met pathway. This allows continued cognitive support without compounding the specific risk associated with Dihexa.

Dihexa Stacking Protocols

Dihexa stacking focuses on complementary mechanisms — pairing HGF/c-Met-mediated synaptogenesis with compounds that support cognition through different pathways. The principle is additive benefit through non-overlapping mechanisms, while avoiding compounds that amplify the same risk profile.

Dihexa + Semax — Synaptogenesis + Neurotrophic Support

The most commonly discussed Dihexa stack. Semax modulates BDNF, NGF, and monoamine neurotransmitters through a mechanism entirely independent of HGF/c-Met. This combination targets neural growth and connectivity from two different angles — Dihexa via HGF/c-Met synaptogenesis and Semax via BDNF/NGF neurotrophic support.

Compound	Dose	Route	Purpose
Dihexa	10–20 mg	SubQ, once daily	HGF/c-Met synaptogenesis, dendritic spine formation
Semax	200–600 mcg	Intranasal, 1–2x daily	BDNF/NGF modulation, focus, neuroprotection

Dihexa + Selank — Cognitive Enhancement + Anxiolysis

Selank provides anxiolytic effects through GABA modulation alongside cognitive support via BDNF pathways. This combination addresses both cognitive performance and the anxiety or stress that can impair it. Selank's calming effect may complement Dihexa's stimulatory cognitive properties.

Compound	Dose	Route	Purpose
Dihexa	10–20 mg	SubQ, once daily	HGF/c-Met synaptogenesis, neural connectivity
Selank	250–500 mcg	Intranasal, 1–2x daily	GABA modulation, anxiolysis, cognitive clarity

Dihexa + BPC-157 — Cognitive + Neuroprotective

BPC-157 has demonstrated neuroprotective properties in animal models, including protection against various neurotoxic insults. Some users combine it with Dihexa for a dual neuroprotective approach — Dihexa promoting new synapse formation while BPC-157 supports neural tissue protection and repair.

Compound	Dose	Route	Purpose
Dihexa	10–20 mg	SubQ, once daily	HGF/c-Met synaptogenesis
BPC-157	250–500 mcg	SubQ, 1–2x daily	Neuroprotection, tissue repair, neural recovery support

Stacking amplifies uncertainty. When combining Dihexa with other compounds, you are creating a protocol with even less evidence than Dihexa alone. Drug interactions between these compounds have not been studied. Stack conservatively, add one compound at a time, and monitor carefully for unexpected effects.

Explore more combinations with our Peptide Stack Builder or browse the Top 10 Peptide Stacks guide.

Safety, Oncological Concerns & Side Effects

This is the most important section of this guide. Dihexa activates the HGF/c-Met signaling pathway, which is a well-established driver of cancer growth and metastasis. This is not a theoretical footnote — it is the central safety consideration that anyone using Dihexa must understand and accept.

The HGF/c-Met Oncological Concern

The hepatocyte growth factor (HGF) and its receptor c-Met are among the most studied oncological targets in modern cancer research. The HGF/c-Met pathway promotes cell proliferation, survival, migration, invasion, and angiogenesis — all hallmarks of cancer progression. Dysregulated HGF/c-Met signaling is implicated in many cancer types including lung, gastric, hepatocellular, renal, breast, and colorectal cancers.

Pharmaceutical companies have invested billions of dollars developing c-Met inhibitors (cabozantinib, crizotinib, capmatinib, tepotinib) specifically to suppress this pathway in cancer patients. Dihexa does the opposite — it activates this pathway.

Key Points on HGF/c-Met Risk:

Established oncological pathway — HGF/c-Met is a validated cancer target. Multiple FDA-approved drugs exist specifically to inhibit this pathway in cancer patients.
No safety data on Dihexa and cancer risk — No studies have measured cancer incidence, tumor biomarkers, or oncological endpoints with Dihexa use in any species over extended periods.
Theoretical risk, not proven harm — There is no direct evidence that Dihexa causes cancer. However, chronically activating a pro-growth, pro-angiogenic pathway implicated in cancer biology is a legitimate concern that cannot be dismissed.
Risk likely increases with duration — Short cycles (2–4 weeks) with adequate breaks carry less theoretical risk than continuous long-term use. This is the primary rationale for cycling.
Pre-existing cancer is a contraindication — Anyone with active cancer, a history of cancer, or elevated cancer risk factors should not use Dihexa under any circumstances.

Reported Side Effects

Side effect data for Dihexa is extremely limited, coming entirely from user reports rather than clinical studies. Reported effects include:

Commonly reported:

Injection site reactions — redness, soreness, minor swelling (common with SubQ injection of any compound)
Headache — reported by some users, particularly in the first few days
Stimulation or difficulty sleeping — some users report feeling overstimulated, particularly with afternoon or evening dosing

Less commonly reported:

Vivid dreams or altered sleep patterns
Mild anxiety or restlessness
Irritability
Fatigue (paradoxical in some users)

Side effect data quality is very low. All reported side effects come from uncontrolled user anecdotes, not from clinical observation. Placebo effects, nocebo effects, and confounding variables (other supplements, lifestyle factors) cannot be separated from genuine Dihexa effects. Do not assume this side effect list is comprehensive — there may be effects that have not been recognized or reported.

Contraindications

Active cancer or history of cancer — HGF/c-Met activation could promote tumor growth, metastasis, and angiogenesis. This is an absolute contraindication.
Elevated cancer risk factors — Strong family history of cancer, known genetic predispositions (BRCA, Lynch syndrome, etc.), or precancerous conditions warrant extreme caution.
Pregnancy and breastfeeding — No safety data exists. HGF/c-Met plays important roles in embryonic development; exogenous activation is unpredictable. Avoid entirely.
Under 25 years of age — Brain development is ongoing through the mid-twenties. Artificially promoting synaptogenesis via HGF/c-Met during neural maturation could have unpredictable consequences.
Liver disease — HGF stands for hepatocyte growth factor. This pathway is heavily involved in liver tissue biology. Pre-existing liver conditions (including hepatocellular carcinoma risk) are contraindications.
Concurrent use of c-Met-targeted cancer therapies — Dihexa would directly counteract c-Met inhibitor cancer treatments.

When to Stop Immediately

Any unusual lumps, growths, or persistent swelling
Unexplained weight loss or persistent fatigue
Severe or persistent headaches not explained by other factors
Significant personality or mood changes
Any symptom that feels abnormal or concerning — err heavily on the side of caution with an unproven compound

Regulatory Status: Dihexa is not FDA-approved for human use. It has no pharmaceutical approval in any country. It is classified as a research chemical. It has not undergone clinical trials, good manufacturing practice (GMP) oversight, or regulatory review. The quality and purity of commercially available Dihexa varies by supplier and is not guaranteed.

Common Dihexa Dosing Mistakes

Avoid these common errors when using Dihexa:

Confusing milligrams with micrograms: Dihexa is dosed in milligrams (mg), not micrograms (mcg). Most peptides are dosed in micrograms, so users accustomed to other peptides may accidentally underdose by a factor of 1,000. Always double-check units. A typical Dihexa dose is 10–20 mg — that is 10,000–20,000 mcg.

Treating the “10 million times more potent than BDNF” claim as proof of nootropic efficacy: This statistic describes in vitro synaptogenic potency in a single cell culture assay. It does not mean Dihexa is 10 million times more effective at improving cognition. Molecular potency at a receptor does not translate linearly to real-world cognitive enhancement. Repeating this claim without context is misleading.

Ignoring the HGF/c-Met oncological risk: The HGF/c-Met pathway is a well-established oncological target. Pharmaceutical companies develop c-Met inhibitors to treat cancer. Chronic activation of this pathway through Dihexa carries theoretical cancer risk that cannot be dismissed. Anyone using Dihexa should understand and accept this risk. It is not a minor footnote — it is the most significant safety concern.

Using Dihexa continuously without cycling: Given the HGF/c-Met safety concern and the complete absence of long-term human safety data, continuous use is not advisable. Standard community protocols recommend 2–4 weeks on followed by 2–4 weeks off. Shorter cycles with adequate breaks are the more prudent approach for an unproven compound.

Assuming animal study results apply directly to humans: All of Dihexa’s efficacy data comes from rat studies and cell culture experiments. Cognitive effects observed in rats with scopolamine-induced impairment may not translate to healthy human cognition. The blood-brain barrier, metabolic clearance, and neural architecture differ significantly between species. Temper expectations accordingly.

Not reconstituting correctly for milligram-scale dosing: Because Dihexa is dosed in milligrams rather than micrograms, the reconstitution math is different from most peptides. You need to calculate concentration carefully to draw accurate volumes. Using too little bacteriostatic water creates very concentrated solutions where small measurement errors have large dosing consequences.

Stacking with multiple HGF/c-Met activators without understanding cumulative risk: If combining Dihexa with other compounds that may influence the HGF/c-Met pathway or growth factor signaling, the cumulative oncological risk is unknown. Stacking should be approached conservatively, and compounds should be chosen for complementary (not redundant) mechanisms.

Starting at the highest reported dose: Without human pharmacokinetic or dose-response data, starting at the upper end of community-reported ranges (20–30 mg) is unnecessarily aggressive. Begin at 5–10 mg daily to assess individual response and tolerance before considering dose increases. There is no clinical evidence that higher doses produce better cognitive outcomes.

Frequently Asked Questions

Key Takeaways

Dihexa is a synthetic peptidomimetic — a modified hexapeptide analog of angiotensin IV that activates the HGF/c-Met pathway to promote synaptogenesis
No human clinical trials exist — all efficacy and safety data comes from animal studies and in vitro experiments. This is one of the least evidence-supported peptides in common use.
Dosed in milligrams, not micrograms: Standard dose is 10–20 mg SubQ daily. Do not confuse mg with mcg — this is a critical distinction.
The “10 million times more potent than BDNF” claim is an in vitro synaptogenic measurement, not a measure of nootropic efficacy. Do not conflate molecular potency with real-world cognitive enhancement.
HGF/c-Met oncological concern is the primary safety issue — this pathway drives tumor growth and metastasis. Pharmaceutical companies develop c-Met inhibitors to treat cancer. Chronically activating this pathway carries theoretical cancer risk.
Cycle strictly: 2–4 weeks on, 2–4 weeks off. Cycling limits cumulative HGF/c-Met exposure.
Common stacks: Semax (BDNF/NGF support), Selank (anxiolysis), BPC-157 (neuroprotection) — all via non-overlapping mechanisms
Start conservatively: 5–10 mg daily for the first cycle; increase only if well-tolerated
Contraindicated in cancer patients — active cancer, history of cancer, or elevated cancer risk factors are absolute contraindications
Not FDA-approved — classified as a research chemical with no pharmaceutical approval in any country

This article is for educational and informational purposes only. See our Disclaimer.

References

McCoy AT, et al. “Evaluation of metabolically stabilized angiotensin IV analogs as procognitive/antidementia agents.” J Pharmacol Exp Ther. 2013;344(1):141-154. PubMed
Benoist CC, et al. “Facilitation of hippocampal synaptogenesis and spatial memory by C-terminal truncated Nle1-angiotensin IV analogs.” J Pharmacol Exp Ther. 2014;351(2):390-396. PubMed
Harding JW, et al. “AT4 receptors: specificity and distribution.” Kidney Int. 1994;46(6):1510-1512. PubMed
Wright JW, Harding JW. “The brain renin-angiotensin system: a diversity of functions and implications for CNS diseases.” Pflugers Arch. 2013;465(1):133-151. PubMed
Organ SL, Bhatt DL. “An overview of the c-MET signaling pathway.” Ther Adv Med Oncol. 2011;3(1 Suppl):S7-S19. PubMed
Gherardi E, et al. “Targeting MET in cancer: rationale and progress.” Nat Rev Cancer. 2012;12(2):89-103. PubMed
Bottaro DP, et al. “Identification of the hepatocyte growth factor receptor as the c-met proto-oncogene product.” Science. 1991;251(4995):802-804. PubMed
Wright JW, Harding JW. “Contributions of matrix metalloproteinases to neural plasticity, habituation, associative learning and drug addiction.” Neural Plast. 2009;2009:579382. PubMed
Birchmeier C, et al. “Met, metastasis, motility and more.” Nat Rev Mol Cell Biol. 2003;4(12):915-925. PubMed
Wright JW, et al. “Angiotensin IV activates hepatocyte growth factor pathway to enhance learning.” Brain Res. 2015;1620:340-349. PubMed

Next Steps

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Dihexa Dosage Guide

Dihexa

What Is Dihexa?

Key Characteristics:

Evidence Limitations — Read This First

What the Research Shows

What Is NOT Known

Where Community Dosing Comes From

How Dihexa Dosage Is Determined

Animal Study Doses

Community-Derived Protocols

Why Milligrams Instead of Micrograms

Standard Dihexa Dosage Ranges

Dosage by Experience Level

Administration Routes

Injection Timing

Nootropic Peptide Comparison

Calculate Your Dihexa Dose

Worked Example:

Quick Reference — 50 mg Vial

Skip the Math — Use Our

Dihexa Dosage by Goal

General Cognitive Enhancement

Neuroprotection & Recovery Support

Conservative / First-Time Protocol

Cycling Protocols

Cycling Protocols

Cycling Rationale

Dihexa Stacking Protocols

Dihexa + Semax — Synaptogenesis + Neurotrophic Support

Dihexa + Selank — Cognitive Enhancement + Anxiolysis

Dihexa + BPC-157 — Cognitive + Neuroprotective

Safety, Oncological Concerns & Side Effects

The HGF/c-Met Oncological Concern

Key Points on HGF/c-Met Risk:

Reported Side Effects

Contraindications

When to Stop Immediately

Common Dihexa Dosing Mistakes

Frequently Asked Questions

What is the standard Dihexa dosage?

Is Dihexa really 10 million times more potent than BDNF?

Has Dihexa been tested in humans?

What are the cancer risks associated with Dihexa?

Why is Dihexa dosed in milligrams instead of micrograms?

Can Dihexa be taken orally or intranasally?

How long does it take for Dihexa to work?

Is Dihexa safe for long-term use?

What is the difference between Dihexa and Semax?

How should Dihexa be stored?

Is Dihexa FDA-approved?

Can Dihexa help with Alzheimer’s disease?

Key Takeaways

References

Next Steps

BPC-157 Dosage Guide

Dosage Calculator

Peptide Directory

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