Cortagen is the brain-cortex member of the Khavinson bioregulator family. It is a synthetic tetrapeptide, Ala-Glu-Asp-Pro (AEDP), designed from the amino-acid composition of Cortexin, a polypeptide extract of animal brain cortex used as a drug in Russia [1]. People take it for brain fog, cognitive aging and recovery after nerve injury, often combined with Pinealon and Epithalon.
My verdict: Cortagen has the most interesting rat data in this family for nerve repair, and almost nothing in people. A single sentence in one paper claims a human benefit for peripheral nerve recovery, but the underlying study is not indexed on PubMed [1].
The peptide bioregulators overview explains the class.
At a Glance
| Property | Detail |
|---|---|
| Sequence | Ala-Glu-Asp-Pro (AEDP), synthetic tetrapeptide |
| Origin | Khavinson group; modelled on the cortex extract Cortexin |
| Proposed mechanism | Gene-regulatory effects in neurons; antioxidant effects in ischaemic brain tissue (rat data) |
| Marketed for | Cognitive aging, brain fog, recovery from nerve injury |
| Route | SC or IM injection; intranasal use reported; the oral brain product in the family is the natural extract Cerluten (Cytomax) |
| Typical dose range | 1–2 mg SC daily for 10–20 days (practice); 10 mg IM daily for 10 days (Khavinson-style protocol) |
| Evidence level | Limited: rat and cell studies from the developer network; no published human trial |
| Regulatory status | Not FDA- or EMA-approved; research chemical; not named by WADA, falls under S0 |
How it works
The group proposes the same mechanism as for the other short peptides: entry into the nucleus and binding to DNA or histones, changing gene expression [2]. Their 2020 review lists AEDP among peptides that push stem cells towards nerve, skin and connective-tissue lineages [2]. In a microarray study, five days of Cortagen injections changed the expression of 110 known genes in mouse heart, partly overlapping with the patterns seen for Epithalon and Vilon [1]. In lymphocytes from people aged 75–88, Cortagen was one of five peptides that loosened tightly packed chromatin in the test tube [3].
Its immune effects look weaker than its siblings’: in mouse cells Cortagen barely raised interleukin-2 mRNA [4] and did not stimulate thymocyte proliferation, where Vilon did [5].
What the evidence shows
Human studies
No PubMed-indexed human trial. The 2004 microarray paper states that “in humans, Cortagen demonstrated a pronounced therapeutic effect” on post-traumatic peripheral nerve recovery [1], without a citation I could trace. A Russian review covers clinical use of cortex peptides in older people but does not report a Cortagen trial with numbers [6].
Animal studies
| Study | Model | Finding |
|---|---|---|
| Turchaninova et al. 2000 [7] | Rats after sciatic nerve transection and suture | 10 µg/kg IM daily for 10 days: regenerating fibres grew 27% faster and conducted 40% faster |
| Kolosova et al. 2002 [8] | Same nerve-injury model | Reported a delayed effect on restoration of nerve function (no abstract available) |
| Zarubina and Shabanov 2011 [9] | Rats with chronic brain ischaemia | Cortagen and Cortexin sped recovery of behaviour and limited lipid peroxidation |
These are small rodent studies from Russian groups, unreplicated elsewhere.
Dosing
For informational purposes only — this summarises doses used in research and practice; it is not a prescription or individual medical advice.
| Goal | Dose | Route | Frequency / timing | Cycle length | Basis |
|---|---|---|---|---|---|
| Cognitive / brain-fog course | 1–2 mg | SC injection | Once daily | 10–20 days (one 20 mg vial), 1–3 courses a year | Practice protocol (r/peptidebioregulators, ZyraTrack forum) |
| Khavinson-style course | 10 mg | IM injection | Once daily | 10 days, 1–2 times a year | Practice protocol (as listed in our bioregulators overview; class dose 5–10 mg on Pepdex) |
| Nerve-injury dose in rats | 10 µg/kg (about 0.1 mg for a 70 kg adult by body-surface scaling) | IM | Once daily | 10 days | Trial (rat) [7] |
| Brain stack | Cortagen + Pinealon + Epithalon | SC or intranasal | Daily | Short courses | Anecdotal (r/Nootropics) |
| Oral alternative (Cerluten, Cytomax) | 1–2 capsules | Oral | 1–2 times daily | 30 days, 1–2 times a year | Label (supplement directions; PeptideDeck summary) |
The rat dose scales to roughly a tenth of the lowest practice protocol and a hundredth of the Khavinson-style course. Nobody knows which is right. Technique: peptide injection guide.
What people report: what works and what doesn’t
Reported to work
- Long-time users of synthetic bioregulators who cycle Cortagen with Pinealon and Epithalon prefer SC injection and say intranasal use also seems to work; specific effects are rarely spelled out (r/Nootropics).
Mixed or unclear
- Community summaries say experiences with brain bioregulators range from “waste of time” to “profound benefits” (r/Nootropics). Cognitive effects are hard to separate from expectation, sleep and caffeine.
Reported not to work / disappointing
- Many users of organ-bioregulator rotations report no noticeable change (Steroidsgrabber forum). No consistent side-effect pattern is described.
A meaningful trial would test nerve-conduction recovery after injury, or validated cognitive scores in older adults, against placebo.
Safety and side effects
- No human safety data in the indexed literature.
- Cognitive decline and nerve injury need diagnosis first. Thyroid, B12, sleep apnoea, depression, medication effects and vascular disease are common and treatable causes.
- Product quality: unregulated vials; hygroscopic short peptides make labelled doses unreliable.
- Pregnancy, active cancer: no data; avoid.
Legal and regulatory status
- US: not FDA-approved; “research use only” means not approved for human use.
- EU / Germany: not authorised as a medicine by the EMA or BfArM.
- Sport: not named on the WADA 2026 list; falls under S0 (non-approved substances).
How it fits
Among brain peptides on this site, Semax and Selank have small Russian clinical trials; Cortagen has rat data. Pinealon has a little more cell and mouse work. For brain fog, a structured work-up beats any peptide; see the brain fog guide.
Related Articles
- Peptide Bioregulators: The Khavinson Protocol and What the Evidence Shows
- Semax: The Nootropic Peptide That Amplifies BDNF
- Selank: The Anxiolytic Peptide from Russia
- Brain Fog Overview
- How to Inject Peptides: A Step-by-Step Guide
Frequently asked questions
What is Cortagen?
Cortagen is the synthetic tetrapeptide Ala-Glu-Asp-Pro (AEDP), designed by Khavinson's group from the amino-acid analysis of Cortexin, a polypeptide extract of animal brain cortex.
Does Cortagen improve memory?
There is no published human trial showing that. The best data are rat studies of nerve regeneration and chronic brain ischaemia.
How is Cortagen different from Pinealon?
Both are marketed for the brain. Cortagen is a tetrapeptide (AEDP) derived from cortex extract; Pinealon is a tripeptide (EDR) with mostly cell-culture and mouse data. Neither has strong human evidence.
What dose of Cortagen is used?
Practice protocols commonly use 1–2 mg SC once daily for 10–20 days. The Khavinson-style protocol referenced on this site is 10 mg a day IM for 10 days, once or twice a year. Neither comes from a dose-finding trial.
Is Cortagen the same as Cortexin?
No. Cortexin is a natural mixture of brain-cortex polypeptides used as a drug in Russia. Cortagen is one synthetic tetrapeptide modelled on it.
References
- Anisimov SV, Khavinson VKh, Anisimov VN. Elucidation of the effect of brain cortex tetrapeptide Cortagen on gene expression in mouse heart by microarray. Neuro Endocrinol Lett. 2004. https://pubmed.ncbi.nlm.nih.gov/15159690/
- Khavinson V, Linkova N, Diatlova A, et al. Peptide Regulation of Cell Differentiation. Stem Cell Rev Rep. 2020. https://pubmed.ncbi.nlm.nih.gov/31808038/
- Khavinson VKh, Lezhava TA, Malinin VV. Effects of short peptides on lymphocyte chromatin in senile subjects. Bull Exp Biol Med. 2004. https://pubmed.ncbi.nlm.nih.gov/15085253/
- Kazakova TB, Barabanova SV, Khavinson VKh, et al. In vitro effect of short peptides on expression of interleukin-2 gene in splenocytes. Bull Exp Biol Med. 2002. https://pubmed.ncbi.nlm.nih.gov/12447482/
- Khavinson VKh, Rybakina EG, Malinin VV, et al. Effects of short peptides on thymocyte blast transformation and signal transduction along the sphingomyelin pathway. Bull Exp Biol Med. 2002. https://pubmed.ncbi.nlm.nih.gov/12420072/
- Umnov RS, Lin’kova NS, Khavinson VKh. Neuroprotective effects of peptides bioregulators in people of various age (in Russian). Adv Gerontol. 2013. https://pubmed.ncbi.nlm.nih.gov/24738258/
- Turchaninova LN, Kolosova LI, Malinin VV, et al. Effect of tetrapeptide cortagen on regeneration of sciatic nerve. Bull Exp Biol Med. 2000. https://pubmed.ncbi.nlm.nih.gov/11276314/
- Kolosova LI, Moiseeva AB, Turchaninova LN, et al. The delayed effect of cortagen on the restoration of injured nerve function. Dokl Biol Sci. 2002. https://pubmed.ncbi.nlm.nih.gov/12134478/
- Zarubina IV, Shabanov PD. Cortexin and cortagen as correcting agents in functional and metabolic disorders in the brain in chronic ischemia (in Russian). Eksp Klin Farmakol. 2011. https://pubmed.ncbi.nlm.nih.gov/21476278/
Disclaimer: This article is for informational and educational purposes only and is not a prescription or individual medical advice. Cortagen is not approved by the FDA or the EMA.
