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Dihexa
Also known as N-hexanoic-Tyr-Ile-(6)-aminohexanoic amide, PNB-0408.
Best known for The Alzheimer's research peptide at an early stage of study
Evidence★☆☆☆☆
Safety dataLargely unknown
Route Oral · transdermal
United StatesNot approved
AustraliaNot listed by name; unapproved therapeutic good
as at 16 September 2026
What it is
Dihexa is a small synthetic peptide derived from angiotensin IV, developed at Washington State University as a candidate treatment for Alzheimer's disease. It has been studied in animals and has not yet entered human trials. Online, it is widely discussed as a nootropic.
What the full entry covers
The book carries the rest of this entry:
- Where the research stands, with every claim cited
- What people commonly ask, and what the research shows so far
- Dosing in four labelled bands, described and not recommended
- Side effects, serious risks, cautions and interactions
- Questions to discuss with your doctor
- How it compares with P21, Semax, Cerebrolysin, DSIP
Related entries
A certificate of analysis tells you what is in a vial. The evidence rating above tells you whether the compound has been shown to work in humans. Neither answers the other's question. How to read a certificate of analysis.
This page describes what is known and not known about Dihexa. It is not medical advice and not a recommendation to use it.