Carl read the papersWhat it actually is
Cortagen is a synthetic tetrapeptide, Ala-Glu-Asp-Pro, from the Khavinson bioregulator family in St Petersburg. It was made by directed synthesis from an amino acid analysis of Cortexin, a Russian prescription drug made from cattle brain cortex.
The family logic is that each short peptide acts preferentially on the tissue it was modelled on. In rat tissue cultures Cortagen did stimulate growth of brain-cortex tissue specifically, and that is the kind of result the whole tissue-specific idea rests on.
How it’s thought to work
- Tissue-specific growth — In rat tissue explants it stimulated growth of brain-cortex tissue, the tissue its parent extract came from.
- Nerve regeneration (rats) — After a sciatic nerve was cut and sutured, 10 days of injections increased the growth rate of the regenerating fibres by 27% and conduction velocity by 40%.
- Brain ischaemia (rats) — Helped rats recover normal behaviour and limited oxidative damage in a chronic brain ischaemia model, much like Cortexin.
- Gene expression — Changed the expression of 110 known genes in mouse heart in a microarray study. What that means for a person is anyone's guess.
What the research says
Rats, mice and tissue cultures, nearly all from the developing group and its collaborators. The most concrete result is the rat sciatic-nerve study: +27% fibre growth rate and +40% conduction velocity after 10 days of injections. A 2004 paper from the same group states that in humans Cortagen showed a pronounced effect on recovery of injured peripheral nerves, but its abstract gives no reference for that, and the 15 Cortagen papers on PubMed are animal and cell studies, with no patient study among them. Nothing is registered on ClinicalTrials.gov.
- Tetrapeptide designed from the amino acid make-up of Cortexin.
- Rat sciatic nerve: +27% regrowth rate, +40% conduction velocity after 10 days of injections.
- Rat ischaemia models: better behavioural recovery and less oxidative damage.
- The human nerve-repair claim is mentioned in passing and not published anywhere traceable.
Reported protocols
These are the doses the peptide community actually reports running (Reddit & forums), alongside published research — logged for education, not as a recommendation to use.
| Parameter | Commonly reported range |
|---|---|
| Community dose | Not established. No independent community reports turned up; the dose figures online come from sellers and do not trace to any human study. |
| Animal studies | Used microgram-per-kilogram injections in rats. Those do not convert into a human dose, so they are context, not a protocol. |
| Route | Injected in the animal work; sold as freeze-dried powder in vials |
| Community tip | When a seller lists a Cortagen 'protocol', it is borrowed from the bioregulator family's habits, not from Cortagen data. |
Common use cases
| Goal | Community protocol notes |
|---|---|
| Research only | nerve and brain recovery are the marketed uses, supported by rat data only |
| Bioregulator sets | sold as the 'cortex' member of the family next to Pinealon |
Mixing it (reconstitution)
Freeze-dried peptides must be reconstituted with bacteriostatic water before they can be measured. Carl’s calculator turns “mg in the vial + ml of water + target dose” into “units on the syringe” — and tells you how long the vial lasts.
→ Open the Reconstitution Calculator
Injection & handling
No established human dose or route. The animal studies gave it by injection; grey-market Cortagen comes as freeze-dried powder in vials. Nothing published tells you how much a person would need, how often, or which side effects to expect, so there is nothing here to follow.
Stacks it appears in
- With Pinealon — Both trace back to Cortexin and are sold as the 'brain' bioregulators.
- With Cerebrolysin — Different products from the same idea. Cerebrolysin is a whole pig-brain extract; Cortexin, Cortagen's parent, is a cattle-brain extract that the Cochrane stroke review counts as Cerebrolysin-like.
Sources
- Anisimov SV et al. Effect of brain cortex tetrapeptide Cortagen on gene expression in mouse heart by microarray. Neuro Endocrinol Lett 2004
- Turchaninova LN et al. Effect of tetrapeptide cortagen on regeneration of sciatic nerve. Bull Exp Biol Med 2000
- Zarubina IV, Shabanov PD. Cortexin and cortagen in chronic brain ischemia. Eksp Klin Farmakol 2011 (Russian)
- Khavinson VK. Tissue-specific effects of peptides. Bull Exp Biol Med 2001
- Ziganshina LE et al. Cerebrolysin for acute ischaemic stroke. Cochrane Database Syst Rev 2023
- Vidal.ru: Cortexin (Кортексин), Russian label
- PubChem: Cortagen (CID 18439621)
- Vidal.ru (Russian drug reference) search: кортаген (Cortagen)
- ClinicalTrials.gov search: cortagen
- SAHPRA: Peptide Products - Public Information (May 2026)
- WADA 2026 Prohibited List
