The analgesic efficiency of morphine and propacetamol for postoperative pain, in the recovery room, was studied in two groups of children, who had undergone either orthopedic or visceral surgery. An injection of 50 mcg/kg of morphine chlorhydrate was given to the first group of 239 children ASA I, who were admitted to the recovery room and who presented signs of severe pain (agitation, crying, complaining). The analgesic efficiency of morphine was judged on physiological criteria (blood pressure, heart rate) and on behavioral criteria (calming of the child). No incidents were noticed. A second study was then performed on a second group of 100 children ASA I, who received 15 mg.kg-1 of propacetamol as an intravenous perfusion for 15 minutes. The analgesic efficiency of propacetamol was judged on behavioral criteria alone. In the morphine group, 67% of the children was calmed following one injection (94% after a second injection given 15 minutes after the first). In the propacetamol group, 77% of the children were calmed. Propacetamol was insufficient for the pain in 23% of the cases but one subsequent injection of morphine was always sufficient to calm the child. These two successive studies show the need for an analgesic protocol for children in the recovery room. Propacetamol should be administered first and then, if insufficient, followed by only one injection of morphine. This protocol of propacetamol and morphine seems to be satisfactory and thus avoids all pernicious side effects.