BACKGROUND Pain management experts have recommended a diminished role for pethidine because of lack of superiority for any indication and greater potential for adverse effects compared with morphine. OBJECTIVES To evaluate the impact of a multifaceted education initiative on prescribing patterns and to minimize pethidine use in the ED. METHODS This was a pre- and post-intervention study. The intervention was an education initiative, introduced between December 2003 and January 2004. It comprised ED pharmacist in-services for medical and nursing staff, championing by senior medical staff (ED consultants, surgical units, Drug and Therapeutics Committee) and concurrent prescriber feedback by ED pharmacists. The pre-intervention prescribing practices guided the development of in-services and the educational programme. The intervention was evaluated by a medical record review of analgesic prescribing in March-April of both 2003 (pre-intervention period) and 2004 (post-intervention period). Outcome measures were the proportions of patients who were prescribed pethidine and the proportions of pethidine ampoules supplied to the ED. Results were analysed as differences in proportions. RESULTS In the pre-intervention period, 60 ampoules of pethidine (7.2% of opiate doses) and 777 ampoules of morphine (92.8% of opiate doses) were administered compared with 15 ampoules of pethidine (1.7%) and 869 ampoules of morphine (98.3%) in the post-intervention period (P < 0.001). Of patients who received an opiate dose, 50 of 798 (6.3%) and 11 of 747 (1.5%) received pethidine in the pre- and post-intervention periods, respectively (P < 0.001). CONCLUSION Our education initiative resulted in a sustained and significant reduction in pethidine prescribing in the ED. Sustainability requires ongoing in-services for ED staff, usually as part of the orientation programme.