Nalbuphine (0.3 mg.kg-1) and buprenorphine (2.5 micrograms.kg-1) were compared as part of a total intravenous anaesthesia regimen using a propofol infusion in 60 patients undergoing laparoscopic cholecystectomy in a randomised double-blind study. Changes in haemodynamic variables greater than 20% from the baseline were noted. No difference was observed in blood pressure but the heart rate was significantly lower in the buprenorphine group. Intra-operative bradycardia (heart rate < 60 beat.min-1) occurred more often in the buprenorphine group. Recovery was fast and comparable with both drugs and no patient reported awareness. Quality of analgesia was similar in both groups. Both drugs provide suitable analgesic supplementation to total intravenous anaesthesia.