Relatives should be asked about the following: The onset and time course of the problem (eg, whether seizure, headache, vomiting, head trauma, or drug ingestion was observed; how quickly symptoms appeared; whether the course has been progressive or waxing and waning) Baseline mental status Recent infections and possible exposure to infections Recent travel Ingestions of unusual meals Psychiatric problems and symptoms Prescription drug history Use of alcohol and other recreational drugs (eg, anesthetics, stimulants, depressants) Previous and concurrent systemic illnesses, including new-onset heart failure, arrhythmias, respiratory disorders, infections, and metabolic, liver, or kidney disorders The last time the patient was normal Any hunches they may have about what might be the cause (eg, possible occult overdose, possible occult head trauma due to recent intoxication) Medical records should be reviewed if available.