CBD for Epilepsy Types Beyond Its Approved Indications | Research

The takeaway

Among 108 patients with various refractory epilepsies treated off-label with CBD, 38.9% achieved at least 50% seizure reduction at three months.

Neurologists, epileptologists, and patients with treatment-resistant epilepsy exploring CBD options.

38.9% of patients with refractory epilepsy achieved 50%+ seizure reduction with off-label CBD

What the researchers found

Add-on CBD showed meaningful seizure reduction across epilepsy types beyond its approved indications (Lennox-Gastaut, Dravet, TSC). At three months, 38.9% of 108 patients achieved at least 50% seizure reduction. Among those with tonic-clonic seizures, 45.8% were 50% responders and 16.7% became tonic-clonic seizure-free. Response was not predicted by sex, age, epilepsy type, or clobazam use.

Why it matters

CBD is only approved for a few rare epilepsy syndromes. This real-world data suggests it may benefit a broader range of patients with treatment-resistant epilepsy, which could support expanded indications.

The numbers in context

108 patients (mean age 27.3, range 1.4-68 years). 38.9% achieved at least 50% seizure reduction at 3 months. 25.9% had 50-74% reduction, 13% had 75-99% reduction. Mean seizure days dropped from 16.8 to 14.5 per month (p=0.002). Retention: 85.2% at 3 months, 73.5% at 6 months, 61.1% at 12 months. 63% rated improved on CGI-C. Adverse events in 38%: diarrhea (15), sedation (13), nausea/vomiting (7).

How the study worked

Retrospective cohort study of 108 patients who started off-label CBD between 2019 and 2023 at six German epilepsy centers. Follow-up included seizure frequency, retention rates, Clinical Global Impression of Change (CGI-C), and adverse events.

What this study cannot tell us

Retrospective design without a control group. Open-label treatment allows for placebo effects and observer bias. Retention was better in children/adolescents, potentially confounding age-related results. Six centers in one country limits generalizability.

How to read the evidence

Multi-center real-world cohort with meaningful sample size, but retrospective, uncontrolled, and open-label design limits causal conclusions.

When this study was published

2025 publication with data from 2019-2023 across six German epilepsy centers.

The bigger picture

The 50% responder rate of 38.9% is comparable to what other anti-seizure medications achieve in registration trials for focal epilepsies, suggesting CBD deserves consideration as a mainstream treatment option rather than a last resort.

Questions still open

Would a randomized controlled trial in focal epilepsy confirm these responder rates?
Why do children and adolescents have better retention on CBD than adults?

Read the original research

Use of cannabidiol for off-label treatment of patients with refractory focal, genetic generalised and other epilepsies.

Neurological research and practice, 7(1), 49

View on PubMed ↗Publisher’s paper ↗

Citation

Hollander, Marie; Mayer, Thomas; Klotz, Kerstin Alexandra; Knake, Susanne; von Podewils, Felix; Kurlemann, Gerhard; Immisch, Ilka; Rosenow, Felix; Schubert-Bast, Susanne; Strzelczyk, Adam. (2025). Use of cannabidiol for off-label treatment of patients with refractory focal, genetic generalised and other epilepsies.. Neurological research and practice, 7(1), 49. https://doi.org/10.1186/s42466-025-00408-w