Dihexa Reference

Plain English

What it is

Dihexa is a lab-made peptide. It is a modified, longer-lasting version of a small piece of a natural body signal called angiotensin IV. Scientists built it to be studied for its effect on the connections between brain cells.

What people use it for

In nootropic (brain-boosting) and post-concussion online communities, people try it hoping to help memory, learning, and brain fog. Because no human studies exist, anything people report is just individual experience, not proof.

What the science shows

The research is almost entirely preclinical, meaning it was done in animals and cells, not people. In mouse models of Alzheimer's it appeared to help spatial learning and memory and to grow new brain-cell connections. One important early study on how it works was later retracted, so even some of the lab evidence is shaky.

The catch

Dihexa is not FDA-approved and is not a treatment for memory loss or cognitive decline. There are no human trials, so its safety and whether it actually works in people are unknown.

Reference summary

Evidence is preclinical, centered on rodent cognition and synaptogenesis models plus medicinal-chemistry work on the AngIV analog. No human clinical efficacy or safety program is established. The foundational paper tying these effects to the HGF/c-Met system (Benoist et al., J Pharmacol Exp Ther 2014;351:390-402) was retracted in 2025 after a Washington State University investigation found falsified or fabricated figure data, which further weakens the mechanistic evidence.

Regulatory and posture

Categories

Cognitive

Aliases

Angiotensin IV analog, N-hexanoic-Tyr-Ile-(6) aminohexanoic amide, PNB-0408

Evidence posture

preclinical - No established human clinical data.

Regulatory status

No FDA-approved Dihexa drug label. FDA lists Dihexa among bulk substances with safety-risk concerns.

Content review status

research reference