What is dihexa?
Dihexa is a lab-made compound based on angiotensin IV, a fragment of a blood pressure hormone, developed at Washington State University. It was designed to be taken by mouth and to reach the brain.
It is sold online as a nootropic for memory and focus.
What does dihexa do?
Dihexa was proposed to boost signaling through the HGF/c-Met pathway, which helps brain cells grow new connections. In rodents, it was reported to improve memory and help brain cells form connections.
What does the research on dihexa show?
All the research is in animals and cells, and part of the foundation has been questioned: a key 2012 paper proposing how it works was retracted in 2024. A related drug from the same research line, fosgonimeton, failed its main Alzheimer’s trial in 2024.
No human trial of dihexa itself has been completed.
Dihexa side effects and risks
Its effects in people are unknown. The pathway it targets also helps cells grow and spread, so researchers have raised theoretical concerns about cancer risk with long-term use. Products sold online aren’t checked for purity or identity.
Is dihexa legal?
Dihexa is not approved for human use anywhere. Its nomination was withdrawn from the FDA’s list of compounding substances with safety concerns, with the FDA noting there was no human exposure data.