Since the first report of epidural opioid administration to pediatric patients, several studies have described the quality of analgesia, doses, pharmacokinetics, and side effects of this procedure. A pediatric series using an easy and cheap single-injection technique of epidural morphine administration for postoperative analgesia is presented. Postoperative analgesia was achieved with a single lumbar epidural morphine injection (0.1 mg/kg in 0.2 mL/kg saline), which was given via a 22-gauge intramuscular needle to 153 pediatric patients (aged 4 months-17 years) following 175 lower abdominal or urologic operations. Injections were given by 43 anesthesiology residents under the supervision of pediatric anesthesiologists, after termination of surgery performed under general anesthesia. The success rate of epidural puncture on the first attempt was 92%. Pain control was considered excellent in 76% of patients for 24 hours. The remaining patients had analgesia lasting 10.9 +/- 5.5 hours after epidural morphine administration. No alterations in hemodynamic parameters were observed. Two patients (1.1%) developed respiratory depression during early postoperative care and one, with a history of apneic spells, had an episode of apnea 5 hours after morphine administration. The incidences of minor side effects were: nausea, 33.9%; vomiting, 42.9%; pruritus 9%; and urinary retention 12.5%. This technique is easy to perform, even for trainees in anesthesiology. With appropriate patient selection and avoidance of the concomitant use of narcotics and sedatives, epidural morphine provides prompt, effective, safe, and prolonged analgesia in children.