Cortexin (Russian: Кортексин, sometimes written Korteksin or Kortexin) is an injectable mixture of polypeptides extracted from the cerebral cortex of livestock. The Russian company GEROPHARM holds its registration and markets it as a “nootropic” for stroke, brain injury, encephalopathy, cognitive impairment and epilepsy in adults, and for learning, speech and developmental problems in children. It was first described in 1999 as “a new peptide bioregulator of cerebral functions” by the St. Petersburg group of V. Khavinson (Khavinson et al., Klin Med 1999).

Like Cerebrolysin, it is not a single molecule and it is not an anabolic agent. Cortexin is registered in Russia and several other former Soviet countries but not in the United States, the UK or the EU. Almost all of the clinical evidence comes from small Russian trials published in Russian, and independent reviewers rate it as weak.

This page summarizes what the Russian product leaflets, clinical trials and systematic reviews report. It is for education only and is not medical advice.

Property	Detail
Drug class	Animal-derived brain peptide preparation, classed in its label as a nootropic
Brand / holder	Cortexin (Кортексин), GEROPHARM LLC, St. Petersburg, Russia
Composition	10 mg of cerebral-cortex polypeptides per vial, as a freeze-dried powder with glycine
Route	Intramuscular injection; a newer form may also be given intravenously to adults with ischemic stroke
Labeled adult dose	10 mg once daily for 10 days; 10 mg twice daily for 10 days in hemispheric ischemic stroke
Half-life	Not established: no human pharmacokinetic data are published, and the patient leaflets give none
US status	Not FDA approved; not named as a controlled substance
WADA status	Not named on the 2026 Prohibited List (see below)

What it is

Both current patient leaflets name the active ingredient as polypeptides from the cerebral cortex of livestock. The leaflet for the intravenous-and-intramuscular form specifies cattle (leaflet, IV/IM form). Reviews describe the source less consistently: the Cochrane review calls Cerebrolysin and Cortexin mixtures purified from cow and pig brains (Ziganshina et al., Cochrane 2023), while another review describes both as peptides isolated from pig brains (Alsulaimani and Quinn, 2021).

Each vial contains 10 mg of the polypeptides, with glycine as the only other listed ingredient (leaflet, IM form). No published analysis lists the individual peptides in Cortexin. This differs from Cerebrolysin, whose peptide content has been profiled by mass spectrometry (see its page).

The leaflets claim that Cortexin’s protein fractions reach the brain directly and that it has nootropic, neuroprotective and anticonvulsant effects. The evidence for these mechanisms comes from animals and the lab:

Brain entry, in mice. Radioactively labeled Cortexin reached brain concentrations of 6–8% of those in whole blood (Kurkin et al., PLoS One 2021).
Receptor binding, in vitro. At 10 µg/mL, Cortexin bound to several glutamate and GABA receptor types, most strongly AMPA receptors (80.1%) and kainate receptors (73.5%). Three of the study’s authors were employees of the company Pharm-Holding.
Synthetic offshoot. Khavinson’s institute designed a synthetic four-amino-acid peptide, Cortagen, from an amino-acid analysis of Cortexin (Anisimov et al., Neuro Endocrinol Lett 2004). Cortagen is a separate compound, and results for one do not apply to the other.

Other peptides promoted for cognition in Russia, such as Semax and Selank, are single defined sequences with their own pages. Cortexin, like Cerebrolysin, is an undefined mixture from animal tissue.

Pharmacokinetics

No human pharmacokinetic study of Cortexin is published, and neither patient leaflet reports a half-life, peak level or elimination route. The only distribution data are the mouse brain-entry figures above. For the comparable mixture Cerebrolysin, the label states that pharmacokinetic parameters cannot be measured directly.

The leaflet for the IV/IM form gives the same dose for people with liver or kidney impairment as for other adults.

Approved medical use

The leaflets list these uses, always “as part of combination therapy”:

Adults: disorders of cerebral circulation; traumatic brain injury and its after-effects; encephalopathy of various causes; cognitive impairment (memory and thinking disorders); acute and chronic encephalitis and encephalomyelitis; epilepsy; asthenic states (fatigue and weakness).
Children and adolescents: reduced learning ability; cognitive impairment; epilepsy; delayed psychomotor and speech development; forms of cerebral palsy.

Patient group	Labeled dose	Labeled duration
Adults, most indications	10 mg once daily	10 days; may be repeated after 3–6 months
Adults, hemispheric ischemic stroke (acute and early recovery)	10 mg twice daily	10 days, repeated after a 10-day break
Children over 20 kg	10 mg once daily	10 days; may be repeated after 3–6 months
Children under 20 kg	Set by the physician by body weight	10 days

The older form is labeled for intramuscular use only, and its leaflet forbids intravenous or subcutaneous injection. The newer form may be given intravenously only to adults with hemispheric ischemic stroke during the first course, with any repeat course given intramuscularly. In children it is labeled for intramuscular use only.

Regulatory status

Russia and neighboring countries. Cortexin is registered by GEROPHARM. Its leaflet lists adverse-event reporting authorities in Russia, Belarus, Kazakhstan, Armenia and Kyrgyzstan. A 2026 analysis of drug registries found it registered across the Commonwealth of Independent States, but not in the US, the UK or the EU (Alexandrova et al., Int J Risk Saf Med 2026). The same analysis found that it is not on the WHO Model List of Essential Medicines.
United States. There is no FDA-approved Cortexin product. It is not listed among the Schedule III anabolic steroids (21 CFR 1308.13).
Sport. Cortexin is not named on the WADA 2026 Prohibited List. The S0 “non-approved substances” class covers only substances with no current approval by any government health authority, and Cortexin is registered in Russia. Whether it could fall under another class has not been settled in any source we found.

What the research shows

Most Cortexin trials were run in Russia and published in Russian, mostly in a single journal, and their English abstracts often give few numbers. Many compared Cortexin added to standard care against standard care alone, with no placebo. We found no controlled trials of Cortexin for muscle growth, athletic performance or recovery from training, so there is no evidence for those uses.

Independent reviews

Review	Cortexin data included	Conclusion
Cochrane 2023, acute ischemic stroke (Ziganshina et al.)	1 RCT, 272 participants, pooled with 6 Cerebrolysin trials	Cerebrolysin or Cortexin probably make little or no difference to death from any cause: RR 0.96 (95% CI 0.65–1.41; 6 trials, 1,689 participants)
Alsulaimani and Quinn 2021, cognitive disorders (Cereb Circ Cogn Behav)	1 RCT, 80 participants	Too few trials for a meta-analysis; certainty of evidence low to very low

The Cochrane reviewers judged the Cortexin trial at low risk of bias for missing outcome data and at unclear risk of bias in every other domain. They also found that Cerebrolysin or Cortexin may make little or no difference to the total number of people with any adverse event (4 trials, 1,607 participants). None of the included trials reported death or dependence at the end of follow-up, quality of life, or return to work.

The cognitive-disorders review found only one eligible Cortexin trial. It enrolled 80 people with mild to moderate cognitive impairment after stroke and gave 10 mg/day for 10 days, repeated at 3, 6 and 9 months, against standard therapy alone. At 12 months the share of patients with a MoCA score (a cognitive screening test) over 26 rose by 27.5% more with Cortexin. MMSE results were not reported, and the reviewers rated the trial at high risk of bias for deviations from the intended treatment. The authors concluded that, across the animal-derived nootropics, effects were modest and “probably less than would be considered clinically relevant.”

Acute ischemic stroke

The only Cortexin stroke trial we found that matches the Cochrane review’s 272 participants is a multicenter, double-blind, placebo-controlled trial (Aliferova et al., 2014). Patients received 10 mg three times a day intramuscularly as two 10-day courses, one course followed by placebo, or two courses of placebo, over 70 days. The abstract reports that two courses worked best but gives no effect sizes.

Other stroke trials were smaller and mostly lacked a placebo:

Trial	Design and n	Arms	Reported result
Belova et al., 2016	90 patients, hemispheric ischemic stroke	20 mg/day for one or two 10-day courses, vs standard therapy alone	Two courses gave the fullest recovery of neurological deficit; no effect sizes in the abstract
Khabirov et al., 2020	40 patients, early recovery after stroke	Cortexin 10 mg/day IM vs the Russian peptide drug Cellex, 10 days each	Cellex did better on the NIHSS stroke scale (p = 0.03) and the MMSE (p = 0.04)
Fedin et al., 2025	490 patients, double-blind, double-dummy	Cortexin IV vs Cortexin IM, then a second IM course in both groups	Good functional outcome (modified Rankin 0–2) at day 90 in 93.6% vs 86.5%; adverse events did not differ

The 2025 trial compared two forms of Cortexin with each other. It had no placebo-only group, so it shows that the forms performed similarly but cannot show that either works better than no treatment.

Chronic cerebrovascular disease and other conditions

Chronic cerebral ischemia. A multicenter trial randomized 189 patients to 20 mg/day, 10 mg/day or standard treatment, for 10 days, repeated after 6 months (Fedin et al., 2018). The authors reported a dose-dependent effect on neurological symptoms, fatigue and sleep. Cognitive gains did not differ between the two doses, and effects on depression and anxiety were described as insignificant.
Type 2 diabetes complications. The DIACORT trial randomized 110 patients to ten 10 mg IM doses plus background glycine and B-vitamin therapy, or background therapy alone (DIACORT, 2026). It reported better cognitive, anxiety, depression and neuropathy scores at 90 days (p under 0.001). No placebo was used, and the PubMed record lists no authors.
Children. In 54 children aged 3–4 with developmental speech disorder (dysphasia), a 10-day IM course was compared with no drug (Zavadenko et al., 2019). Speech scales improved more with Cortexin, but the comparison group received no placebo.

Animal studies

Animal results conflict, and they do not show what the drug does in people:

Study	Model	Cortexin result
Zhang et al., J Neurol Sci 2019	Embolic stroke in rats, blinded comparison of four brain-peptide products, 10 days	Functional outcome no better than saline; infarct 33.5% vs 30.8% with saline (not significant). Only Cerebrolysin improved function
Kurkin et al., PLoS One 2021	Acute and chronic brain ischemia in rats, 1 or 3 mg/kg/day for 10 days	Better neurological recovery and smaller area of dead tissue in acute ischemia
Shchulkin et al., 2026	Stroke with reperfusion in rats, single 1 mg/kg dose	Dead tissue 32.8% vs 38.2% in controls (p = 0.198, not significant); no change in BDNF; lower TNF-α and some markers of cell death

Side effects and risks

Labeled adverse effects

The leaflets list all of the following as very rare (no more than 1 in 10,000 people):

Type	Reported effects
Severe allergic	Anaphylactic shock; angioedema of the larynx (swelling that can block the airway)
Skin and injection site	Drug allergy, hives, rash, itching, allergic dermatitis; redness and warmth at the injection site; pain and hardening at the site after IM injection (IV/IM form)
Heart and circulation	Fast heart rate, arrhythmia, raised blood pressure
Nervous system and mood	Psychomotor agitation, poor coordination, headache, dizziness, drowsiness, anxiety, insomnia, fatigue, chills; reduced skin sensation (IV/IM form)

Because agitation and dizziness can occur, the leaflets advise caution when driving. In the IV-versus-IM stroke trial, 60 of 246 patients in the IV group had at least one adverse event, compared with 41 of 244 in the IM group, a difference the authors reported as not significant.

The trials are small and short, and most did not use a placebo. Rare harms, including allergic reactions to an animal-tissue product, could be missed in studies of this size.

Who should not use it

The leaflets list these contraindications:

hypersensitivity to Cortexin or its ingredients;
pregnancy;
breastfeeding.

Women using it are advised to use contraception.

Interactions

Lidocaine: the leaflets warn against using lidocaine as the diluent, because of possible adverse reactions.
Procaine: procaine (novocaine) is one of the listed diluents for IM use, so procaine allergy should be reported before treatment.
Other solutions: the prepared solution should not be mixed with other solutions.

The leaflets list no drug-drug interactions beyond these.

Products from outside the regulated supply

No Cortexin product is approved in the US, so any Cortexin sold there is outside the FDA-regulated drug supply. It is an injectable product made from animal tissue, and its composition cannot be checked by the buyer.

Key takeaways

A brain-peptide mixture, not a single drug. Cortexin is an undefined set of polypeptides from livestock cerebral cortex, sold in Russia as a nootropic.
Registered in Russia and the CIS, not in the US, UK or EU. There is no FDA-approved product.
No known half-life. No human pharmacokinetic data are published.
Weak human evidence. Most trials are small, Russian-language and unblinded. Independent reviewers rate the evidence as low to very low certainty, and Cochrane found no effect on death after stroke.
Conflicting animal data. One blinded rat study found no benefit over saline, while a study co-authored by employees of a drug company found protective effects.
No evidence for muscle or performance. No controlled trials have tested it for training, recovery or athletic use.

Sources

GEROPHARM LLC. Cortexin, 10 mg, lyophilisate for solution for intramuscular injection: patient information leaflet (in Russian). korteksin.ru.
GEROPHARM LLC. Cortexin, 10 mg, lyophilisate for solution for intravenous and intramuscular injection: patient information leaflet (in Russian). korteksin.ru.
Khavinson VKh, Morozov VG, Rybnikov VIu, et al. Cortexin effectiveness in circulatory encephalopathy (in Russian). Klin Med (Mosk). 1999;77(4):42–45. PubMed.
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;25(1-2):87–93. PubMed.
Ziganshina LE, Abakumova T, Nurkhametova D, Ivanchenko K. Cerebrolysin for acute ischaemic stroke. Cochrane Database Syst Rev. 2023;10(10):CD007026. PubMed.
Alsulaimani RA, Quinn TJ. The efficacy and safety of animal-derived nootropics in cognitive disorders: systematic review and meta-analysis. Cereb Circ Cogn Behav. 2021;2:100012. PubMed.
Alexandrova EG, Abakumova TR, Ziganshina LE. Use of nootropics in Alzheimer’s disease: an analysis of regulatory positions and drug policies in the countries of the Commonwealth of Independent States. Int J Risk Saf Med. 2026;37(2):257–264. PubMed.
Aliferova VM, Dadasheva MN, Doronin BM, et al. Clinical efficacy and pharmacoeconomic characteristics of the neuroprotection with low doses of cortexin in the treatment of acute ischemic stroke (in Russian). Zh Nevrol Psikhiatr Im S S Korsakova. 2014;114(4):41–46. PubMed.
Belova LA, Mashin VV, Abramova VV, et al. Efficacy of cortexin in acute and recovery periodes of hemispheric ischemic stroke (in Russian). Zh Nevrol Psikhiatr Im S S Korsakova. 2016;116(10):38–42. PubMed.
Khabirov FA, Khaibullin TI, Granatov EV, et al. Comparison of the efficacy of Cellex and Cortexin in patients in the early recovery period of ischemic stroke (in Russian). Zh Nevrol Psikhiatr Im S S Korsakova. 2020;120(12 Vyp 2):11–15. PubMed.
Fedin AI, Khairova EN, Artyukov OP, et al. Therapeutic equivalence of intravenous and intramuscular dosage forms of Cortexin in ischemic strokes (in Russian). Zh Nevrol Psikhiatr Im S S Korsakova. 2025;125(12):60–67. PubMed.
Fedin AI, Belskaya GN, Kurushina OV, et al. Dose-dependent effects of cortexin in chronic cerebral ischemia (results of a multicenter randomized controlled study) (in Russian). Zh Nevrol Psikhiatr Im S S Korsakova. 2018;118(9):35–42. PubMed.
Cortexin in the comprehensive treatment of neurological complications of type 2 diabetes mellitus. (Results of the DIACORT multicenter randomized clinical trial) (in Russian; no authors listed). Zh Nevrol Psikhiatr Im S S Korsakova. 2026;126(4):101–112. PubMed.
Zavadenko NN, Davydova LA, Suvorinova NY, Khondkaryan GS. Potential of peptidergic nootropic therapy in developmental dysphasia in children (in Russian). Zh Nevrol Psikhiatr Im S S Korsakova. 2019;119(11):47–53. PubMed.
Zhang L, Chopp M, Wang C, et al. Prospective, double blinded, comparative assessment of the pharmacological activity of Cerebrolysin and distinct peptide preparations for the treatment of embolic stroke. J Neurol Sci. 2019;398:22–26. PubMed.
Kurkin DV, Bakulin DA, Morkovin EI, et al. Neuroprotective action of Cortexin, Cerebrolysin and Actovegin in acute or chronic brain ischemia in rats. PLoS One. 2021;16(7):e0254493. PubMed.
Shchulkin AV, Chernykh IV, Abalenikhina YV, et al. The effect of neuroprotectors on the level of BDNF, tumor necrosis factor alpha and apoptosis markers, and in acute cerebrovascular accidents (in Russian). Zh Nevrol Psikhiatr Im S S Korsakova. 2026;126(2):123–129. PubMed.
World Anti-Doping Agency. The 2026 Prohibited List. WADA 2026 Prohibited List.
US Code of Federal Regulations. 21 CFR 1308.13, Schedule III. 21 CFR 1308.13.

Cortexin