Efficacy and Tolerability of Nolotil i.v. vs. Placebo i.v. in the Prevention of Postoperative Pain in Children Undergoing Minor Surgery

Inclusion Criteria: * Children of either sex between 6 and 11 years of age * Patients undergoing routine inguinal hernia repair or tonsillectomy * Written informed consents by the guardian, according to the guidelines of Good Clinical Practice and current legislation * The ability of the patient to understand and carry out the visual analogue scale assessments * Patients with a physical status American Society of Anesthesiologist I or II class Exclusion Criteria: * The use of any drug with analgesic properties in the 24 hours prior to the administration of the study drug * Surgery with a foreseen duration over 60 minutes * Patients with a nutritional index of less than 90 or greater than 120 * Patients with a body mass index which was not between the 3rd centile and the 97th centile for age * Patients with any illness or malformation (except hernia) which, in the doctor's opinion, contraindicated the use of metamizol (aplastic anemia, agranulocytosis of a toxicological etiology, severe renal disease, etc.) * Patients who have received in the previous 7 days or need currently anticoagulant treatment * Significant allergy or known hypersensitivity to metamizol, its excipients and/or to other nonsteroidal antiinflammatory drugs * Patients in whom the anesthetic regimen required by the protocol cannot be used * Patients who have participated in another clinical trial in the past four weeks or are currently participating in another clinical trial * Patients with any psychological disturbance which, in the investigator's opinion makes the patient unsuitable for inclusion in the trial