CBD reduced seizures in children with severe epilepsy beyond just Dravet and Lennox-Gastaut syndromes

Among 78 children and young adults with refractory epilepsy, 31% achieved 50% or greater seizure reduction at 3 months, with Dravet and Lennox-Gastaut patients responding best (70%) and clobazam co-medication improving outcomes.

Zilmer, Monica et al.·Danish medical journal·2021·Moderate EvidenceRetrospective Cohort
RTHC-03644Retrospective CohortModerate Evidence2021RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Retrospective Cohort
Evidence
Moderate Evidence
Sample
N=78

What This Study Found

At 3 months, 31.4% of patients achieved 50% or greater seizure reduction and 68.6% showed some improvement. Dravet and Lennox-Gastaut patients had much higher response rates (70% achieving 50% reduction) compared to other epilepsies (22%). Clobazam co-medication increased seizure reduction. Response rates declined over time: 20% maintained 50% reduction at 24 months.

Key Numbers

Patients: 78. With seizure registration: 51. 50% reduction at 3 months: 31.4%. At 6 months: 31.1%. At 12 months: 28.1%. At 24 months: 20.0%. Dravet/LGS at 3 months: 70%. Other epilepsies: 22%. Any reduction at 3 months: 68.6%.

How They Did This

Retrospective cohort study of 78 patients treated with off-label cannabidiol at the Filadelfia Epilepsy Hospital, Denmark from 2016-2019. Assessed seizure frequency registration or perceived effect over up to 24 months.

Why This Research Matters

While CBD is approved for Dravet and Lennox-Gastaut syndromes, this study shows it may also benefit children with other severe epilepsies, though the waning response over time needs monitoring.

The Bigger Picture

The declining response over time (from 31% to 20% achieving 50% reduction) suggests tolerance may develop, reinforcing the need for ongoing evaluation and willingness to discontinue if benefits fade.

What This Study Doesn't Tell Us

Retrospective, uncontrolled design. Off-label use with varying doses. Only 51 of 78 patients had seizure frequency registration. No placebo comparison.

Questions This Raises

  • ?Is the declining response over time due to tolerance or natural disease progression?
  • ?Would higher CBD doses maintain efficacy?
  • ?What factors predict which non-Dravet/LGS patients respond?

Trust & Context

Key Stat:
70% of Dravet/LGS patients achieved 50%+ seizure reduction at 3 months
Evidence Grade:
Real-world clinical data with up to 24 months follow-up, but uncontrolled retrospective design.
Study Age:
Published in 2021 with data from 2016-2019.
Original Title:
Cannabidiol treatment of severe refractory epilepsy in children and young adults.
Published In:
Danish medical journal, 68(5) (2021)
Database ID:
RTHC-03644

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-ControlFollows or compares groups over time
This study
Cross-Sectional / Observational
Case Report / Animal Study

Looks back at existing records to find patterns.

What do these levels mean? →

Frequently Asked Questions

Does CBD work for epilepsies other than Dravet and Lennox-Gastaut?

In this study, 22% of patients with other severe epilepsies achieved 50% or greater seizure reduction at 3 months, lower than Dravet/LGS (70%) but still meaningful.

Does CBD effectiveness last over time?

Response rates declined from 31% at 3 months to 20% at 24 months, suggesting some tolerance development and the importance of ongoing monitoring.

Read More on RethinkTHC

Cite This Study

RTHC-03644·https://rethinkthc.com/research/RTHC-03644

APA

Zilmer, Monica; Olofsson, Kern. (2021). Cannabidiol treatment of severe refractory epilepsy in children and young adults.. Danish medical journal, 68(5).

MLA

Zilmer, Monica, et al. "Cannabidiol treatment of severe refractory epilepsy in children and young adults.." Danish medical journal, 2021.

RethinkTHC

RethinkTHC Research Database. "Cannabidiol treatment of severe refractory epilepsy in child..." RTHC-03644. Retrieved from https://rethinkthc.com/research/zilmer-2021-cannabidiol-treatment-of-severe

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.