A year of CBD cut seizures in half for many drug-resistant epilepsy patients

A retrospective study out of Spain, published in Epilepsia Open, followed 37 adults with severe, drug-resistant epilepsy — Dravet syndrome, Lennox-Gastaut syndrome and tuberous sclerosis complex — for a median of 28 months on CBD treatment. At the 12-month mark, 45.9% had cut their seizure frequency by at least half, and 59.5% had a reduction of at least 25%.

Caregivers also reported better alertness and behavior in nearly 30% of patients, and the median number of other antiseizure medications patients were taking dropped from four to three — a meaningful detail for a patient population that's usually already cycling through drug combinations with diminishing returns.

It wasn't free of downsides: about 65% of participants had some adverse event, mostly mild things like drowsiness, though a few saw liver enzyme changes or irritability, and six of the 37 patients stopped treatment altogether over side effects or lack of benefit. Thirty of the 37 were still on CBD at the one-year mark.

The authors are upfront about the limits: small sample, no control group, retrospective design, and patients often changed other medications at the same time, so CBD can't be cleanly credited for every improvement. It adds to a growing pile of real-world evidence that CBD helps some drug-resistant epilepsy patients, without being the randomized, controlled proof that would settle the question.