Propofol (mean dose 2.85 mg kg-1 h-1) was administered for 4 days by continuous i.v. infusion for sedation in 14 agitated and restless ICU patients. This provided rapid control of the level of sedation. When the infusion was discontinued, adequate recovery with response to commands was obtained in most patients by 10 min. Recovery times and the decrease in blood propofol concentration were similar after 24, 48, 72 and 96 h of infusion. Cumulative effects, tachyphylaxis, or other untoward effects were not observed.