Dihexa
Also known as: N-hexanoic-Tyr-Ile-(6) amino hexanoic amide · PNB-0408 · PNB-1046
Dihexa is a small angiotensin IV-derived peptide developed by Joseph Harding's lab as a potential Alzheimer's therapeutic. Acts through the HGF/c-MET pathway to drive spinogenesis. Not approved anywhere; sold in the research-chem space.
Last reviewed · Panya.health editorial
Panya scores vendors against an 11-signal rubric. Vendors at or above 70 out of 100 are routable; below 70 are documented but get no Panya affiliate link. For prescription peptides like Mounjaro and Wegovy, Panya routes today through licensed clinicians. For research peptides like Dihexa, vendor scorecards land in a follow-up sprint after legal review and payment processor selection. Until then, the page surfaces commonly-mentioned vendor names so adults can do their own diligence. We do not yet earn commission on any Dihexa vendor.
Not medical advice. Dihexa is not approved for human medical use in most jurisdictions. The data below is what users do; it is not what regulators have validated. You decide your risk profile.
What it does, and how
Dihexa was developed at Washington State University from the parent compound angiotensin IV, which had shown nootropic effects in earlier rodent work. The active species is a hexanoic-acid-flanked dipeptide that is orally bioavailable and crosses the blood-brain barrier. Mechanistically it acts as a hepatocyte growth factor (HGF) potentiator: dihexa binds HGF and amplifies signaling at the c-MET receptor, which drives dendritic spine formation in hippocampal neurons. Harding's published work showed dihexa to be roughly 7 orders of magnitude more potent than BDNF in spinogenesis assays in rat hippocampal slices. The Alzheimer's-model rodent data was promising on cognitive endpoints; human trials were filed but never reached published Phase 1 readouts.
Typical practice
Community practice runs 8 to 45 mg per day, oral, in 4 to 8 week cycles. Most users dose once daily on an empty stomach because dihexa is described as orally active in the rodent work. Some stack with semax or noopept for cognitive synergy on the assumption that BDNF + spinogenesis hit different mechanisms; this stacking is not validated in humans. There is no established dose-response curve in humans. Whatever you find online about 'optimal' dosing is extrapolated from one species at one body weight.
The dosing above is community practice, not a regulator-validated protocol. Trial-validated dosing for Dihexa in humans does not exist for most use cases listed.
Risks and contraindications
The biggest concern is the same mechanism that makes dihexa interesting: HGF/c-MET signaling. This pathway is heavily implicated in cancer biology. c-MET amplification is a known driver in lung, gastric, hepatocellular, and renal cancers; HGF/c-MET inhibitors are an active oncology drug class precisely because the pathway promotes tumor growth, invasion, and metastasis. A potent HGF amplifier with no human safety data is therefore a real bet against an unknown personal cancer-risk profile. Anyone with a history of cancer, family history of any of those tumor types, or known c-MET-amplified disease should not touch this. Standard rules also apply: pregnancy and breastfeeding off-limits, no human cardiovascular safety data, no known interaction profile, no quality control on what's sold under this name.
Where this stands legally
FDA has not approved dihexa for human use. Sold legally as a research chemical 'not for human consumption.' Not on the 503A bulks list, so compounding pharmacies cannot legitimately compound it. WADA-banned via the S0 'non-approved substances' clause for athletes.
Not a controlled substance. MHRA does not regulate research peptides; sale is technically lawful but human use is medically unsupervised. Customs scrutiny on bulk imports has tightened; small personal-use orders sometimes pass.
Not on EMA's approved list. Treated as a research chemical in most member states. Cross-border imports occasionally seized at customs; legal exposure varies by member state.
TGA treats unapproved peptides as Schedule 4 (prescription-only) by default. Personal-use imports of research peptides are actively investigated. Don't import without a prescription you won't get.
Not formally scheduled. Available through research-peptide channels and a small number of Bangkok wellness clinics that import for nootropic clients. FDA Thailand has not enforced against personal use as of 2026.
MOHAP treats unapproved peptides as prescription-only by default. Personal-use imports require a doctor's letter and are commonly held at customs. Do not ship via courier without paperwork.
Where users say they source it
Names below are sourced from community discussion. None are currently scored against the Panya 11-signal rubric. Panya does not earn commission on any of these. You can search them yourself; treat the list as a starting point for your own diligence, not an endorsement.
- Pure RawzPending Panya 11-signal audit
- Limitless Life NootropicsPending Panya 11-signal audit
- AminolabsPending Panya 11-signal audit
- Cosmic NootropicPending Panya 11-signal audit
Full vendor scorecards for Dihexa land in a follow-up sprint after lawyer review and payment processor selection. We will not route users to any vendor that scores below 70 on the rubric.
Papers worth reading directly
- McCoy et al. — Evaluation of metabolically stable angiotensin IV analogs as procognitive / antidementia therapeutics. J Pharmacol Exp Ther, 2013 →
- Benoist et al. — Facilitation of hippocampal synaptogenesis and spatial memory by C-terminal truncated Nle1-angiotensin IV analogs. J Pharmacol Exp Ther, 2014 →
- Wright et al. — The brain hepatocyte growth factor / c-MET receptor system: a new target for the treatment of Alzheimer's disease. J Alzheimers Dis, 2017 →
- Gherardi et al. — Targeting MET in cancer: rationale and progress. Nat Rev Cancer, 2012 (oncology context for the c-MET pathway) →
Panya blog posts
The phrase on every grey-market peptide site. What it actually means, what it does not mean, and why reading it wrong costs people money.
The five things that matter on a COA, the three things that do not, and the one question that separates a serious vendor from a cargo-cult operator.
The clinic route costs more and takes longer. The research-chem route puts more on you. Neither is wrong. Here is how to choose.
Adjacent reading
Track Dihexa in your peptide journal.
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