Levetiracetam (LEV) is a broad-spectrum antiepileptic drug with no known interactions and a favorable profile of adverse events. These properties make it a good candidate for use in critically ill patients. An intravenous formulation of LEV was recently approved. The present study retrospectively assesses the safety and efficacy of LEV in the first 50 critically ill patients treated with intravenous LEV. Indications for use were seizure prophylaxis, acute symptomatic seizures, and all forms of status epilepticus. There were no major adverse effects, although less prominent changes may have been masked by the already severely compromised condition of these patients. Two patients (4%) had transiently lowered platelet counts (55,000 and 82,000, respectively). Efficacy, defined as cessation of seizure activity or prevention of its recurrence, was observed in 41 of 50 patients (82%). Antiepileptic treatment of critically ill patients with LEV seems to be effective and safe according to the data for this small cohort, but this observation warrants further prospective investigation in a larger number of patients.