Epilepsy & Seizures
Epilepsy and specific seizure disorders represent the most robustly evidenced application of cannabis medicine, with FDA-approved pharmaceutical CBD (Epidiolex) demonstrating significant seizure reduction in clinical trials.
Quick Reference
Epidiolex — The Landmark Approval
Epidiolex is a pharmaceutical-grade CBD oral solution approved by the FDA in 2018 for Dravet syndrome and Lennox-Gastaut syndrome — two severe, treatment-resistant childhood epilepsy syndromes. This approval represented a watershed moment in cannabis medicine, as it was the first FDA approval of a cannabis-derived medicine. Clinical trials showed Epidiolex reduced seizure frequency by 39-47% compared to 14% for placebo in Dravet syndrome patients. It is now approved in the US, EU, and UK for these conditions.
CBD's Anti-Epileptic Mechanisms
CBD's anti-epileptic effects operate through several mechanisms: it inhibits voltage-gated sodium channels (the same target as established anti-epileptic drugs), modulates GABA receptors to reduce neuronal excitability, activates GPR55 receptors which regulate neuronal calcium signalling, and reduces inflammation in the brain. Importantly, CBD's anti-epileptic action appears to be largely independent of CB1 receptors — explaining why pure CBD is effective without producing psychoactive effects.
Beyond Dravet and LGS
Research is ongoing for CBD in other seizure types. There is growing evidence for benefit in tuberous sclerosis complex (TSC) — Epidiolex received FDA approval for TSC in 2020. CDKL5 deficiency disorder, Aicardi syndrome and other treatment-resistant epilepsies are also being studied. In real-world use, families with children with intractable epilepsy frequently report dramatic seizure reductions with cannabis preparations, and this patient-led evidence was a major driver of the formal clinical trial programme.
Important Considerations
Epilepsy treatment requires specialist neurological input — do not modify anti-epileptic medication regimens without specialist guidance. CBD interacts significantly with clobazam (a common anti-epileptic), increasing its blood levels and effects. Drug monitoring is essential when starting CBD in patients on existing anti-epileptics. THC-containing preparations are generally not recommended for epilepsy management — THC can in some cases lower seizure threshold. Only use pharmaceutical-grade CBD for epilepsy management, not unregulated products.