How often is antiseizure drug-free ketogenic diet therapy achieved?

The ketogenic diet (KD) is often started not only for seizure reduction but also to potentially wean antiseizure drugs (ASDs) in children with epilepsy. Although there have been several publications regarding ASD reduction on the KD, it is unknown how often complete medication withdrawal occurs. We reviewed the charts of all children started on the KD at Johns Hopkins Hospital and Johns Hopkins All Children's Hospital from 1/11 to 4/18. Children were defined as achieving drug-free diet (DFD) status if they started the KD on at least 1 ASD and achieved a period of time where they were on the KD alone. Over the time period, 232 children were evaluated; DFD status occurred in 43 (18.5%), of which 32 (13.8% of the full cohort) remained off ASDs for the remainder of their KD treatment course. Eleven children restarted ASD after a mean of 7 months. Children achieving DFD therapy were more likely to be younger, have fewer ASDs at KD onset, have Glut1 deficiency or epilepsy with myoclonic–atonic seizures, but were less likely to have Lennox–Gastaut syndrome or a gastrostomy tube.