Dihexa

A lab-made "brain" chemical sold for memory. It has only been tested in animals. The FDA found no data from people.

FDA statusNot approved

Not an FDA-approved medicine. This alone does not tell you if it works.

Proof it works in people for memory and brain powerAnimal or lab only

Tested in rats and mice, not people.

Safety data in peopleVery little

No data in people, says the FDA.

These are 3 different questions. FDA status is about the law. Proof is about whether it works. Safety data is about how much we know about its risks. A lack of safety data does not mean it does not work, and "not approved" does not mean "illegal."

By the Peptide Science Desk Editorial TeamFact-checked against FDA and official sources · Oct 28, 2026Not yet reviewed by a licensed clinician. How we check facts

What is it?

Dihexa is a lab-made chemical built from a peptide. Scientists made it from a body signal called angiotensin IV.

Why do people use it?

Some people use it hoping to boost memory or brain power. These are claims. They are not proven facts.

Does it really work?

Tests in rats and mice suggest it may help memory. But the FDA says it found no data at all on people using dihexa, in any form. Results in animals often do not hold up in people.

Key studies (none in people)

Study	People	What they found	Limits
Mouse study	Mice with memory loss	Mice did better on memory tests.	Mice, not people.

We found no published study that tested this in people. The rows above are not studies of Dihexa itself in people.

We only list studies we read on PubMed or ClinicalTrials.gov. Checked October 18, 2026.

Is it safe? Side effects

The FDA found no data on people using dihexa.
The FDA says it does not know if dihexa would cause harm in people.
Ask a doctor before you try any product that claims to boost the brain.

Is it legal in the US?

Dihexa is not an FDA-approved medicine.

The FDA had put Dihexa on its "Category 2" list: things that may be too risky for a pharmacy to mix into a medicine.
In April 2026, Dihexa was moved off that list because the groups that had asked the FDA about it took back their request. The FDA did not say it is safe.
Dihexa is also not on the list of things regular pharmacies are allowed to mix.
On October 28, 2026, HHS issued a peptide policy for 6 other peptides. It does not cover Dihexa.

(The FDA is the US agency that checks if medicines are safe and work.)

What "not approved" does and does not mean

"Not FDA approved" is not the same thing as "illegal." It means the FDA has not reviewed proof that it works and is safe.
Outside the narrow pharmacy rules below, selling it as a medicine for people breaks federal law. The FDA has warned companies that sold unapproved drugs labeled "for research" or "not for human consumption" to people. (FDA)
A regular pharmacy may only mix (compound) a drug from a raw ingredient that has an official quality standard, is part of an FDA-approved drug, or is on the FDA’s 503A list. Big "outsourcing" pharmacies (503B) have their own list. (FDA)
The FDA says that in most cases it is illegal for people to bring unapproved drugs into the US for their own use. (FDA)
State rules differ. State boards of pharmacy oversee most pharmacies day to day. Sports leagues and the military have their own bans. (FDA)

Banned in sports? Drug tests

Not named, but may be banned.

Dihexa is not named on WADA's list. But WADA says its list is not complete. It also bans any drug that is not approved for people by any government anywhere (section S0). From Jan 1, 2027, that rule names "peptides" too. Ask USADA before you use it.

Check work, NCAA, and military rules for Dihexa

Talk to your doctor

Do not start any peptide on your own. Ask a doctor first. We never share doses or tell you where to buy. Print our doctor questions sheet.

Check any peptide in 1 secondFree FDA Status Checker: approved, being tested, or not proven.

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Not medical advice. Medical disclaimer.