Dihexa
N-hexanoic-Tyr-Ile-(6) aminohexanoic amide — angiotensin IV analogue
An orally active angiotensin IV analogue that promotes synapse formation in laboratory models. It has never been tested in humans, and it acts on a pathway with well-known cancer relevance.
- Category
- Cognitive
- Half-life
- Not established in humans
- Cycle length
- Not established — no human protocol exists
- Level
- advanced
Overview
Dihexa is a synthetic analogue of angiotensin IV, designed to cross into the brain and to act on the hepatocyte growth factor pathway. In rodent studies it produced synapse formation and improvements on memory tasks at very low doses — results striking enough to make it a fixture of nootropic discussions for over a decade. It has also never been given to humans in a published trial. That gap is what defines it: the most compelling findings come from animals, and the pathway it activates is one that oncology researchers watch closely for other reasons.
How it works
Dihexa is reported to potentiate the activity of hepatocyte growth factor by binding to its receptor, c-Met, which is involved in cell growth, survival and the formation of new synaptic connections. In cell and animal models this produced measurable synaptogenesis and improved performance on memory and learning tasks. Angiotensin IV activity on the renin–angiotensin system also contributed to its design rationale.
Reported benefits
- Increased synapse formation in laboratory models
- Improved performance on memory and learning tasks in rodents
- Orally active in animal studies, unusual for a peptide
- Effective at very low doses in preclinical work
Reported benefits describe what the published literature and user reports suggest — not a promise of outcome for any individual.
Dosing reference
There is no established human dose. Preclinical studies used small oral or injected doses in rodents, typically in the low milligram per kilogram range; no human trial has been published.
Any human figure circulating for dihexa is derived from animal work with no dose-finding or pharmacokinetic study in people. There is no basis for a safe starting dose.
Community-reported figures vary widely: 5–20 mg orally or transdermally once weekly is the most common pattern, with some reporting daily use. No human pharmacokinetic data exists, so no reported figure has a sound basis.
These figures are what people report using in public communities. They have not been studied, verified or checked against certificates of analysis, and they are not a recommendation, a prescription or a target to aim for.
Where the reported amounts come from
Amounts are reproduced for education only. Doses from trials cannot be assumed to suit anyone else, and community-reported amounts are frequently wrong. Self-administering unapproved compounds carries serious risk.
The research picture
Dihexa's profile comes from a small number of studies published in the 2010s describing synaptogenesis and enhanced memory in rodents and in cell culture. The findings were notable because of the low doses involved and because the compound was orally bioavailable, and they generated considerable enthusiasm. What has not happened is the next step: no phase 1 study, no human pharmacokinetics and no safety data. Meanwhile c-Met is a pathway implicated in tumour growth, so chronic activation of it is a theoretical risk that nobody has examined in people. It is a genuinely interesting research molecule and not a reasonable self-experiment.
Preclinical & non-clinical data
Derived from angiotensin IV; rodent studies show new hippocampal synapse formation and improved learning through hepatocyte growth factor signalling. Oral and injected routes have been used in rodents only — there is no human study of any kind.
Non-clinical data comes from cells and animals unless stated otherwise. It answers whether a compound is worth studying in people — not whether it is safe or effective in them.
What users report
Nootropic reports describe it as strong and distinctly different: mood elevation and verbal fluency on one side, and headaches, anxiety and an unpleasant overstimulated feeling on the other. Effects are usually reported within days rather than weeks. Both oral and transdermal routes appear in accounts, and users openly argue about which actually delivers anything. This is the compound in the index with the widest gap between enthusiasm and any formal safety data.
Where these reports come from
These are unverified personal accounts collected from public sources. They are not evidence of effectiveness or safety, they have not been independently checked, and they are not a recommendation to use anything described.
Possible side effects
- No human adverse-event data exists
- Unknown consequences of activating the c-Met pathway in people
- Injection-site reactions and sterility risks if supplied as a powder
- Unknown interactions with any medication
Safety notes
No human safety data of any kind. Because dihexa acts on c-Met, a pathway involved in cell proliferation in several cancers, long-term activation is a plausible theoretical concern for anyone with a history of malignancy. The absence of even a phase 1 trial means there is no evidence about dose tolerance, organ effects or drug interactions.
Stacking
Frequently discussed alongside other nootropic compounds, none of which have been studied with it. Combining unapproved compounds with unknown pharmacology multiplies unquantified risks.
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