We have conducted a randomized, double-blind study in 255 ASA I and II patients to compare the efficacy of lignocaine and metoclopramide in minimizing the pain of injection of i. v. propofol. When administered immediately before propofol into a dorsal hand vein, compared with placebo both drugs significantly reduced the incidence of pain on subsequent injection of propofol (P < 0.007). Twenty patients who had received metoclopramide (n = 85) experienced pain, compared with 18 who had received lignocaine (n = 85) and 42 who had been pretreated with saline (n = 85).