In a double-blind study the effect of a single IV dose (25 mg) of chlorpromazine on gastric emptying, as determined by the rate of paracetamol absorption, was measured in seven healthy volunteers. Each volunteer acted as his/her own control. There was no significant difference between the maximum paracetamol concentration, the time to reach the plasma maximum concentration, and the area under the plasma concentration time curve from 0-120 minutes on the two occasions, indicating unchanged gastric emptying after administration of chlorpromazine.