We investigated the efficacy and safety of midazolam given intravenously for the treatment of status epilepticus in children. Patients received one to three bolus injections of midazolam (0.15 to 0.40 mg/kg) until seizures disappeared completely. In other patients, continuous infusion of midazolam (0.06 to 0.48 mg/kg/hr) followed a bolus of midazolam or other anti-epileptic agents. The dose was increased every 15 minutes until the seizures were brought under control. The etiology of 62 episodes of status epilepticus was epilepsy in 43, acute encephalopathy/encephalitis in 11, febrile seizures in 7 and hypoxic encephalopathy in 1. The age of the patients ranged from 0.2 to 18.4 years (average: 3.7 years). Bolus injections were administered in 53 episodes. The average loading dose was 0.35 +/- 0.22 mg/kg (range 0.15 to 0.90 mg/kg). Of the 42 episodes in which seizures disappeared, 13 required no further continuous infusions. Of the remaining 29 in which continuous infusion was done at the rate of 0.06 to 0.60 mg/kg/hr (mean 0.30 mg/kg/hr), 21 ended in cessation of the seizures. The duration of continuous infusions ranged from 4 to 288 hours (average 49.0 hours). In 6 episodes there were adverse effects:transient hypoxemia (5) and agitation during withdrawal (1). No intervention was needed except oxygenation by mask for less than 72 hours. Midazolam is effective and safe, and can be used as the first line drug in the treatment of status epilepticus in children.