OBJECTIVES: To investigate the possible advantage of administration of preemptive oral ibuprofen in children after ambulatory pediatric urologic surgery such as penile surgery (circumcision and hypospadias repair) and inguinal surgery (communicating hydrocele and orchidopexy), a study was performed on the experience of postoperative pain, nausea or vomiting, and resumption of normal activities such as normal sleep and play activity. In addition, this study has validated a method of measurement of pain and resumption of normal activities in children. MATERIAL AND METHODS: In a prospective, randomized, double-blind study, 66 prepubertal boys (0-12 years) underwent an ambulatory pediatric urological intervention. One hour prior to surgery, the experimental group received 10 mg/kg oral ibuprofen along with their usual premedication (<8 years midazolam 0.5 mg/kg PO or rectal; >8 years or >30 kg alprazolam 0.5 mg, 0.25-0.5 mg PO), whereas the children of the control group received only the usual premedication. Anesthesia was achieved with Sevorane((R)) (Sevoflurane) inhalation induction (Sevoflurane 8% in 50% N(2)O/50% O(2)) and a locoregional caudal block (0.5-1.0 ml/kg levobupivacaine 0.25% with a maximum of 30 ml). Immediate postoperative pain was assessed by the child, the parents and a single observer using the Faces Pain Scale and the CHEOPS behavioral scale (Children's Hospital of Eastern Ontario Pain Scale). Vomiting and nausea were also assessed. On the first and second postoperative day the same variables were evaluated by the child and the parents, as well as quality of sleep and play, and need for pain medication. RESULTS: No difference in the experience of pain was found at any point after the operation between the experimental and control groups; moreover, the consumption of pain medication postoperatively did not differ between the two groups. There was also no difference in the incidence of vomiting and nausea in the hospital or at home (p>0.05). The method for measuring pain and normal activities was validated as the assessments of the parents, children and the investigators were concordant throughout the study. CONCLUSIONS: Children who received preoperative oral ibuprofen (10 mg/kg) did not experience less pain or less nausea and vomiting, and did not show a better pattern of sleep and play up to 2 days after ambulatory pediatric urologic surgery than children who did not receive this medication.