Purified CBD Reduced Seizures in 92% of Children With Drug-Resistant Epilepsy | Research

The takeaway

A multicenter Israeli study of 139 children with drug-resistant epilepsy found 92% had reduced seizures on purified CBD, with 41% achieving over 50% reduction. Prior response to CBD oil predicted response to purified CBD.

Pediatric neurologists, epilepsy specialists, and families of children with seizure disorders

92% had reduced seizures, 41% achieved >50% reduction

What the researchers found

92.2% of patients had reduced seizure frequency after starting purified CBD. 41.1% achieved >50% reduction. 38.1% had additional positive effects including improved alertness (31.7%), improved speech (10.1%), and new developmental milestones (2.2%). Prior success with CBD oils, especially >50% reduction, strongly predicted purified CBD response. Common adverse events were irritability (20.9%) and drowsiness (12.9%).

Why it matters

This real-world evidence from 5 medical centers confirms the clinical trial findings for purified CBD in a broader, more diverse patient population. The finding that prior CBD oil response predicts purified CBD response is clinically useful for treatment planning.

The numbers in context

139 patients. Median age 12 years. LGS 37.4%, Dravet 16.5%, TSC 16.5%. Median dose 12.5 mg/kg (range 2.5-20). Median treatment 9 months. 92.2% seizure reduction. 41.1% >50% reduction. Adverse: irritability 20.9%, drowsiness 12.9%.

How the study worked

Retrospective multicenter analysis of 139 children and young adults (54.7% female, median age 12.0 years) with drug-resistant epilepsy treated with purified CBD at five Israeli medical centers from 2018-2022. Median dose 12.5 mg/kg, median duration 9 months.

What this study cannot tell us

Retrospective design with potential selection bias. No control group. Seizure frequency was clinically assessed, not by EEG monitoring. Some patients may have had concurrent medication changes. Cannot determine the contribution of placebo effect.

How to read the evidence

Multicenter real-world study with reasonable sample size, but retrospective design and lack of control group limit causal conclusions.

When this study was published

2024 study using 2018-2022 data

The bigger picture

As purified CBD (Epidiolex) becomes available in more countries, real-world effectiveness data is needed alongside clinical trials. This study confirms effectiveness across multiple epilepsy syndromes and identifies a practical predictor of treatment success.

Questions still open

Why do some patients respond to CBD oil but not purified CBD, or vice versa? Is the 12.5 mg/kg median dose optimal? Would longer follow-up show sustained benefit or tolerance?

Common questions

Does purified CBD help children with drug-resistant epilepsy?

In this study of 139 children, 92% had reduced seizures on purified CBD and 41% had their seizures cut by more than half. The most common diagnoses were Lennox-Gastaut, Dravet, and tuberous sclerosis.

Can CBD oil response predict purified CBD success?

Yes. Children who previously responded well to CBD oils, especially those with >50% seizure reduction, were significantly more likely to also respond to purified CBD.

Read the original research

Real-Life Experience With Purified Cannabidiol Treatment for Refractory Epilepsy: A Multicenter Retrospective Study.

Pediatric neurology, 150, 91-96

View on PubMed ↗Publisher’s paper ↗

Citation

Tzadok, Michal; Gur-Pollack, Rotem; Florh, Hadar; Michaeli, Yael; Gilboa, Tal; Lezinger, Mirit; Heyman, Eli; Chernuha, Veronika; Gudis, Irina; Nissenkorn, Andreea; Lerman-Sagie, Tally; Ben Zeev, Bruria; Uliel-Sibony, Shimrit. (2024). Real-Life Experience With Purified Cannabidiol Treatment for Refractory Epilepsy: A Multicenter Retrospective Study.. Pediatric neurology, 150, 91-96. https://doi.org/10.1016/j.pediatrneurol.2023.10.012