Prospective study of the efficacy of a ketogenic diet in 20 patients with Dravet syndrome.

•Patients with Dravet syndrome were placed on a ketogenic diet (KD) for 6 months.•Of the 20 patients, 17 exhibited ≥50% decreases in seizure frequency on the KD.•On the KD, no generalised convulsions ≥5 min or status epilepticus was detected.•The KD also improved patients’ cognitive function.•The KD is a good treatment option for medically intractable epilepsy.