Head to head
Dihexa against Semax
An experimental peptide with striking animal potency claims against a peptide with small human trials. Dihexa has never been given to a person in a published study, which is the only comparison that matters before dosing either.
Column A
DihexaDihexa (angiotensin IV analogue)
An experimental angiotensin-derived peptide reported to be an extremely potent promoter of new synapse formation in animal models of cognition.
Column B
SemaxSemax (synthetic ACTH 4-10 analogue)
A synthetic heptapeptide approved in Russia for stroke and cognitive disorders, studied for BDNF-driven neuroprotection.
Side by side, on the facts we can check
| Attribute | Dihexa | Semax |
|---|---|---|
| Category | Nootropic & CNS | Nootropic & CNS |
| FDA status | Not FDA-approved; experimental | Not FDA-approved (approved in Russia and Ukraine). PCAC voted to recommend for compounding (July 2026); awaiting FDA rulemaking |
| Half-life | Short | Short (minutes); intranasal use |
| Molecular weight | ~564 Da | 813.9 Da |
| Mechanism | Potentiates hepatocyte growth factor and its c-Met receptor to drive synaptogenesis, the formation of new synaptic connections. | Increases BDNF and NGF expression and modulates the melanocortin and dopaminergic systems, supporting neuroprotection and synaptic plasticity. |
| Human studies cited | 0 | 1 |
| Legal status, US | Not approved; research use only | Not approved; research use only |
Frequently asked questions
What is the difference between Dihexa and Semax?
Dihexa: An experimental angiotensin-derived peptide reported to be an extremely potent promoter of new synapse formation in animal models of cognition. Semax: A synthetic heptapeptide approved in Russia for stroke and cognitive disorders, studied for BDNF-driven neuroprotection.
Which has stronger research evidence, Dihexa or Semax?
This database does not grade compounds. It counts what was run in people: 0 of the 2 studies cited on the Dihexa profile were human work, against 1 of 4 for Semax. Those counts are of our own citation lists and understate any larger literature, and neither is a recommendation.
Are Dihexa and Semax FDA-approved?
Dihexa: Not FDA-approved; experimental. Semax: Not FDA-approved (approved in Russia and Ukraine). PCAC voted to recommend for compounding (July 2026); awaiting FDA rulemaking.
Related posts
Blog articles that cover Dihexa or Semax, newest first.
- Research / Sep 8, 2026 / 9 minPeptides for Sleep: DSIP, Epitalon and Pinealon Against the Evidence
- Safety / Sep 8, 2026 / 9 minPeptide Side Effects by Class: What Is Documented, What Is Anecdotal
- Regulation / Sep 8, 2026 / 9 minFDA Peptide Status in 2026: The Category 2 Removals, the July Votes, and What Actually Changed
Reviewed Sep 2026. This page sets two published records side by side. It is educational, it is not medical advice, and it contains no dosing protocols or recommendations for personal use.