Brain & sleep Angiotensin IV-derived peptide
Dihexa
Regulatory status
Status at a glance
503A compounding status
Not nominated
We found no pending nomination for the 503A bulks list. Unless the substance has another legal pathway (for example, a USP monograph or use in an FDA-approved drug), 503A pharmacies generally may not compound with it.
- Also known as
- the Research Peptide
- FDA approval
- Not FDA-approved for any use
- 503B outsourcing
- Not determined
- Anti-doping (WADA)
- Not on the WADA Prohibited List
- DEA schedule
- Not a controlled substance
About peptide status
Most peptides discussed here are not FDA-approved for any use, and products labeled “research use only” are not for human use. Removal from Category 2 does not authorize compounding. PCAC votes are non-binding recommendations; FDA and HHS make the final decisions.
This is not medical or legal advice, and we do not publish dosing, sourcing or reconstitution information. Talk with a licensed clinician before using any peptide.
If you think you are having a medical emergency, call 911.
Key takeaway
Dihexa is an experimental cognition peptide derived from angiotensin IV, sold on the "research peptide" market for brain function. Its evidence is entirely preclinical, with no human trials, and a key paper describing its proposed mechanism has been retracted. As of 2026 it is not FDA-approved or approved anywhere.
At a glance
- FDA status
- Non-FDA-approved peptide sold as a research chemical
- What it is
- Angiotensin IV-derived peptide studied for cognition in animals
- Research
- Preclinical only; no human trials, and a key mechanism paper was retracted
- Approval status
- Not approved anywhere
- Evidence strength
- Low research
Summary
Dihexa is an experimental angiotensin IV-derived peptide with no human trials and a retracted mechanism paper. See what the research shows and its legal status.
What is dihexa?
Dihexa is a synthetic peptide derived from angiotensin IV, designed to be taken orally and cross into the brain. It was developed in academic research as a candidate for cognitive disorders and is sold through "research chemical" channels for brain function and memory. It is not an approved medicine.
How does it work?
Dihexa has been proposed to promote the formation of new connections between nerve cells by enhancing a growth-factor pathway in the brain (hepatocyte growth factor and its receptor, c-Met). An important caveat belongs here: the primary research paper describing this mechanism has since been retracted, which weakens even the preclinical rationale. The remaining supporting data are from cell and rodent experiments. This describes a proposed mechanism, separate from any demonstrated benefit in people.
Is it FDA-approved?
Safety note
Status: Non-FDA-approved peptide sold as a research chemical
Category: Wellness and performance · Primary body area: Brain & sleep
No. Dihexa is not approved by the FDA or by any regulator. It is not on FDA compounding lists and was not among the peptides reviewed at the 2026 FDA compounding advisory meetings.
What does the research show?
Editor’s note
Evidence strength: Low research
There are no human data at all, and the key paper underlying its proposed mechanism has been retracted, so even the preclinical rationale carries an added reliability concern.
The evidence is preclinical, and partly compromised. Animal experiments (such as maze-based memory tests) have been reported, but the foundational mechanism paper has been retracted, and there are no completed human efficacy trials. There is no sound human evidence that dihexa improves cognition.
Sources: general reference literature on therapeutic peptides noting the absence of clinical trials for dihexa (Journal of the AAOS Global Research & Reviews, 2025, DOI: 10.5435/JAAOSGlobal-D-25-00236), indexed on PubMed; the retraction of the primary dihexa mechanism paper is noted in the PubMed record. This document is educational, is not medical advice or a health claim, and is not an offer to sell any product.
Registered human trials
0 registered human trials on ClinicalTrials.gov that we reviewed
Sources
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- [2]
- [3]
- [4]
- [5]
- [6]
- [7]
- [8]
- [9]
- [10]
- [11]
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