CBD has better antiepileptic potential than THC and is FDA-approved for Dravet and Lennox-Gastaut syndromes, but it has significant drug-drug interactions and can cause liver enzyme elevation, especially with valproate.
Epilepsy patients and families, neurologists prescribing CBD, and healthcare policy researchers.
CBD causes liver enzyme elevation when combined with valproate
What the researchers found
CBD modulates multiple endogenous systems for anticonvulsant effects. It has broad drug interactions with CYP3A4 and CYP2C19 substrates. Liver enzyme elevation occurs especially when co-administered with valproate. FDA-approved pharmaceutical-grade CBD is expensive and schedule V, while other CBD products remain schedule I and unregulated.
Why it matters
Many families are turning to CBD for epilepsy, but the practical reality is complicated by drug interactions, cost, regulatory inconsistency, and the risk of unregulated products.
The numbers in context
FDA approved for Dravet and Lennox-Gastaut syndromes. Drug interactions with CYP3A4 and CYP2C19 substrates. Liver enzyme elevation with valproate co-administration. Pharmaceutical CBD reclassified as schedule V.
How the study worked
Narrative review of CBD's clinical efficacy, mechanism of action, drug interactions, regulatory status, and practical challenges for epilepsy treatment.
What this study cannot tell us
Narrative review. Does not include its own meta-analysis. The exact anticonvulsant mechanism remains unknown.
How to read the evidence
Moderate: comprehensive clinical review of established evidence and regulatory landscape.
When this study was published
Published in 2019.
The bigger picture
The gap between FDA-approved pharmaceutical CBD and the unregulated CBD market creates a two-tier system where patients who cannot afford or access the approved product may turn to products of unknown quality.
Questions still open
- Will insurance coverage expand beyond Dravet and Lennox-Gastaut? Can unregulated CBD products achieve similar results? How should physicians manage drug interactions in patients already on multiple antiepileptics?
Common questions
Is all CBD the same for epilepsy?
What are the most important drug interactions?
Read the original research
Cannabidiol: A Review of Clinical Efficacy and Safety in Epilepsy.
Pediatric neurology, 96, 24-29
Citation
Samanta, Debopam. (2019). Cannabidiol: A Review of Clinical Efficacy and Safety in Epilepsy.. Pediatric neurology, 96, 24-29. https://doi.org/10.1016/j.pediatrneurol.2019.03.014
Explore the wider topic
- CBD Oil Quality Guide: How to Avoid Snake Oil
- Anxiety After Quitting Weed: When to Consider Medication
- Cannabis for Chemotherapy Nausea: What the Evidence Actually Shows
- Cannabis for Chronic Pain: What the Research Actually Supports
- Cannabis and Epilepsy: The Epidiolex Story and What It Means
- Does CBD Actually Work for Anxiety? What the Evidence Shows
- Does CBD Help with Weed Withdrawal? What Studies Show
- CBD vs THC: The Differences That Actually Matter
- The Proven Medical Benefits of Cannabis: What Research Supports
- Quitting Weed Before Surgery
- Weed and Medications: What Changes When You Quit
- Quitting Weed During Pregnancy: What You Need to Know
- Quitting Weed While Pregnant: What You Need to Know
- Cannabis and Older Adults: Risks Seniors Should Know
- Cannabis and Breastfeeding: THC in Breast Milk