CBD (cannabidiol) & Epilepsy

Written based on 33 research studies on PubMed, searched on 2026. nov. 11..

The claim

Posts online say that CBD (cannabidiol) helps with epilepsy.

Where research stands

We found 475 published papers on CBD (cannabidiol) and epilepsy. They were published between 1974 and 2026. 47 of them are studies in people. 25 of them compared people who got it with a group that did not. 66 were studies in animals, and 4 were only in cells in the lab. 122 papers are reviews that sum up other studies. 8 new studies in people are running or will start soon, say the trial registers. 7 research projects on CBD (cannabidiol) for epilepsy are funded and still running. CBD (cannabidiol) is approved for epilepsy in the EU, the US and Switzerland.

• 47In people25 with a comparison group
• 66In animals
• 4Only in the lab

What the studies found

We have not summed up these studies in words yet. The most important papers are listed under Sources.

Verdict

Sources

1. Clinically Meaningful Reduction in Drop Seizures in Patients with Lennox-Gastaut Syndrome Treated with Cannabidiol: Post Hoc Analysis of Phase 3 Clinical Trials.2025 · CNS Drugs · Randomised trial
2. Use of cannabidiol for off-label treatment of patients with refractory focal, genetic generalised and other epilepsies.2025 · Neurol Res Pract · Randomised trial
3. Establishment of a point of departure for CBD hepatotoxicity employing human HepaRG spheroids.2023 · Toxicology · Randomised trial
4. Adjunctive Transdermal Cannabidiol for Adults With Focal Epilepsy: A Randomized Clinical Trial.2022 · JAMA Netw Open · Randomised trial
5. Long-term cannabidiol treatment for seizures in patients with tuberous sclerosis complex: An open-label extension trial.2022 · Epilepsia · Randomised trial
6. Add-on cannabidiol in patients with Dravet syndrome: Results of a long-term open-label extension trial.2021 · Epilepsia · Randomised trial
7. Long-term safety and efficacy of add-on cannabidiol in patients with Lennox-Gastaut syndrome: Results of a long-term open-label extension trial.2021 · Epilepsia · Randomised trial
8. Time to onset of cannabidiol (CBD) treatment effect in Lennox-Gastaut syndrome: Analysis from two randomized controlled trials.2021 · Epilepsia · Randomised trial
9. Long-term efficacy and safety of cannabidiol in patients with treatment-resistant focal epilepsies treated in the Expanded Access Program.2025 · Epilepsia · Study in people
10. Concomitant cannabidiol does not impact safety and effectiveness of diazepam nasal spray for seizure clusters: Post hoc analysis of a phase 3 safety study.2023 · Epilepsy Behav · Study in people
11. Effects of Cannabidiol on Adaptive Behavior and Quality of Life in Pediatric Patients With Treatment-Resistant Epilepsy.2022 · J Clin Neurol · Study in people
12. Effect of Cannabidiol on Interictal Epileptiform Activity and Sleep Architecture in Children with Intractable Epilepsy: A Prospective Open-Label Study.2021 · CNS Drugs · Study in people
13. Seizure frequency, quality of life, behavior, cognition, and sleep in pediatric patients enrolled in a prospective, open-label clinical study with cannabidiol.2021 · Epilepsy Behav · Study in people
14. Cannabidiol in pediatric drug-resistant epilepsies: A systematic review and meta-analysis of seizure responder rates and neurobehavioral outcome reporting.2026 · Epilepsy Res · Review
15. Nanostructured lipid carriers for intranasal cannabidiol delivery in Dravet and Lennox-Gastaut syndromes: bridging preclinical promise to clinical translation.2026 · Ther Deliv · Review
16. A systematic review of highly purified cannabidiol in developmental and epileptic encephalopathies and complex treatment-resistant epilepsies: Nonseizure outcomes.2026 · Epilepsy Res · Review
17. Cannabidiol and epilepsy: therapeutic, mechanistic and clinical significance.2026 · Seizure · Review
18. Cannabidiol Use in Developmental and Epileptic Encephalopathies: A Syndrome- and Age-Stratified Systematic Review and Meta-analysis.2026 · CNS Drugs · Review
19. Adjunctive Cannabidiol for Drug-Resistant Epilepsy: A Systematic Review and Meta-Analysis of Randomized Trials Across Syndromes, Formulations, and Dose Ranges.2026 · Ther Clin Risk Manag · Review
20. Comparative analysis of the effects of Δ9-tetrahydrocannabinol and cannabidiol on pilocarpine-induced status epilepticus in mice.2026 · Neuroscience · In animals
21. Subchronic Cannabidiol (CBD) Treatment During the Silent Period Fails to Prevent Increased Seizure Susceptibility Following Lithium-Pilocarpine-Induced Status Epilepticus.2026 · Brain Sci · In animals
22. Cannabidiol attenuates seizure progression and recognition memory deficit induced by hippocampal HCN1 knockdown in the kindling model of epilepsy in male rats.2026 · Neuropharmacology · In animals
23. Chronic oral cannabidiol delays seizure onset and reduces seizure burden in a mouse model of CLN2 disease.2026 · PLoS One · In animals
24. Cannabidiol reduces atypical absence seizures and epileptic spasms in a Gabrb3+/D120N mouse model of Lennox-Gastaut syndrome.2026 · Epilepsia Open · In animals
25. In Vivo Characterization of Synthetic Cannabidiol Analogs for Seizure Suppression in Zebrafish.2026 · ACS Chem Neurosci · In animals
26. Cytotoxicity and Immunomodulatory Effects of Cannabidiol on Canine PBMCs: A Study in LPS-Stimulated and Epileptic Dogs.2024 · Animals (Basel) · In the lab
27. Cannabidiol (CBD) Alters the Functionality of Neutrophils (PMN). Implications in the Refractory Epilepsy Treatment.2021 · Pharmaceuticals (Basel) · In the lab
28. Differential Inhibition of Human Nav1.2 Resurgent and Persistent Sodium Currents by Cannabidiol and GS967.2020 · Int J Mol Sci · In the lab
29. Aberrant epilepsy-associated mutant Nav1.6 sodium channel activity can be targeted with cannabidiol.2016 · Brain · In the lab
30. Long-Term Drop-Seizure Response Patterns to Cannabidiol According to Genetic Status in Lennox-Gastaut Syndrome.2026 · CNS Neurosci Ther · Other paper
31. Editorial: Cannabidiol: perspectives on drug-resistant epilepsy management.2026 · Front Pharmacol · Other paper
32. Use of purified cannabidiol as add-on therapy in children with non-self-limited focal epilepsies of childhood: A multicenter study.2026 · Epilepsy Behav · Other paper
33. Cannabidiol in Adults With Lennox-Gastaut Syndrome: Real-World Experience.2026 · Eur J Neurol · Other paper