An elderly case of consciousness disturbance due to levetiracetam and low doses of carbamazepine

Abstract

It is challenging to discern whether consciousness disturbances experienced by an epilepsy patient are due to insufficient pharmacological activity of antiepileptic drugs or medication side effects. We treated an 82-year-old man with epilepsy who experienced a cerebellar infarction, followed by renal impairment due to a right renal infarction, and had decreased serum albumin levels. His consciousness disturbance persisted for more than two months. The disturbance improved one day after termination of levetiracetam administration. Re-administration of levetiracetam resulted in recurrence of consciousness disturbance. When carbamazepine was administered, he experienced consciousness disturbance despite a low blood concentration of 3.0 μg/mL. Drug-monitoring methods are well established for carbamazepine, but levetiracetam is a novel antiepileptic drug. This case report suggests that in patients with renal impairment and hypoalbuminemia, levetiracetam and low doses of carbamazepine may cause sporadic adverse effects such as consciousness disturbance.