The authors retrospectively review their experience in children with the latest addition to the postoperative analgesic armamentarium: interpleural analgesia (IPA). IPA was used in 14 children following thoracotomy. There were 9 boys and 5 girls. Patients varied in age from 2 months to 17 years 4 months (mean +/- SEM = 7.6 +/- 1.6 yr). Catheters were left in place from 10 to 72 hours (mean +/- SEM = 45.1 +/- 4.6 h). Four patients received intermittent bolus doses and 10 patients received a continuous infusion through the interpleural catheters. Adequate analgesia, as judged by both subjective responses (decreased irritability or complaints of pain) and by objective physiologic responses (decreased heart rate, respiratory rate, and systolic blood pressure), was achieved in 13 of 14 patients. Eight of the 14 children required no additional analgesic agents. One child received 2 doses of oral codeine and 4 patients received 2 to 3 doses of intravenous narcotic during IPA. IPA was not effective in one patient who required 6 doses of intravenous meperidine. Patients more than 10 years of age required significantly more (P < 0.05) intravenous narcotic supplementation than patients less than 10 years of age (1.60 +/- 0.50 v 0.14 +/- 0.11 mg meperidine/kg/d). No complications related to placement or subsequent use of IPA were identified in any of the patients. IPA provides effective postoperative analgesia following thoracotomy in children.