--Disease Characteristics-- Status epilepticus with at least 5 minutes of sustained seizure activity with a depressed level of consciousness, or 2 or more discrete seizures without recovery or consciousness between seizures Verified by bystander or observed by paramedic from San Francisco Department of Health --Prior/Concurrent Therapy-- No chronic benzodiazepines for seizure disorder --Patient Characteristics-- Cardiovascular: Systolic blood pressure at least 100 mm Hg No second- or third- degree atrioventricular block No sustained ectopic tachyrhythmia Pulse rate between 60 and 150 No severe myocardial insufficiency No hypovolemic, cardiogenic, or obstructive shock Pulmonary: No history of asthma No history of chronic obstructive airway disease No history of limited pulmonary reserve Other: No allergy or prior sensitivity to benzodiazepines No distributive shock (e.g., septic, neurogenic, or anaphylactic)