The only FDA-approved cannabis-derived medicine (Epidiolex) is for epilepsy.
Epilepsy affects 3.4 million Americans and is characterized by recurrent, unprovoked seizures. Approximately 30% of patients have drug-resistant epilepsy — seizures that do not respond to two or more antiseizure medications. CBD (as Epidiolex) is FDA-approved for Dravet syndrome, Lennox-Gastaut syndrome, and tuberous sclerosis complex, representing the gold standard of cannabis medicine evidence.
3.4 million
Americans Affected
1.2% of U.S. population
Prevalence
2
Key Studies
3
Cannabinoids Reviewed
CBD (as pharmaceutical Epidiolex) is FDA-approved for three epilepsy syndromes. The pivotal NEJM trial (2017, n=120) showed CBD reduced convulsive seizures by 38.9% vs. 13.3% placebo in Dravet syndrome. CBD's anticonvulsant mechanisms are distinct from all existing antiseizure medications, making it effective in drug-resistant cases.
CBD antagonizes GPR55, a receptor that promotes neuronal excitability. GPR55 blockade reduces the excessive neuronal firing that underlies seizures. This mechanism is distinct from all existing antiseizure medications.
CBD desensitizes TRPV1 channels, which regulate neuronal excitability. TRPV1 overactivation contributes to seizure generation, and CBD's desensitizing effect reduces seizure threshold.
CBD inhibits adenosine reuptake, increasing extracellular adenosine levels. Adenosine is an endogenous anticonvulsant that reduces neuronal excitability via A1 and A2A receptors.
CBD modulates voltage-gated sodium channels — the target of many existing antiseizure medications — providing an additional anticonvulsant mechanism that may contribute to its efficacy in drug-resistant epilepsy.
Epidiolex (pharmaceutical CBD) is FDA-approved for Dravet syndrome, Lennox-Gastaut syndrome, and tuberous sclerosis complex. Dose: 5–20mg/kg/day. Requires medical supervision.
CBDA shows anticonvulsant activity in preclinical models at doses 100x lower than CBD. May be relevant for drug-resistant epilepsy. Human trials pending.
THC can both reduce and provoke seizures depending on dose and seizure type. Not recommended for epilepsy management without specialist guidance.
CBD for Drug-Resistant Seizures in Dravet Syndrome
CBD reduced convulsive seizures by 38.9% vs. 13.3% placebo (p=0.01) in 120 Dravet syndrome patients. Five patients became seizure-free.
CBD in Treatment-Resistant Epilepsy
Median 36.5% reduction in monthly motor seizures across multiple drug-resistant epilepsy syndromes in 214 patients.
Dosing information is for educational purposes only. Always start with the lowest effective dose and consult a healthcare provider before use.
Start Dose
2.5mg/kg twice daily
Target Dose
10–20mg/kg/day
Timing
Twice daily with food
FDA-approved pharmaceutical. Requires prescription and medical supervision. Monitor liver enzymes. Interacts with clobazam (increases levels).