['To determine whether oral dextromethorphan (1 mg/kg) given one hour prior to surgery decreases opioid administration in the perioperative period in children undergoing tympanomastoid surgery.', 'This was a prospective randomized double-blinded and placebo-controlled study in which 20 male and 18 female children (age 11.5 +/- 3.5 years) were enrolled. Nineteen children received dextromethorphan (DM), while the other 19 received placebos. Postoperative pain was assessed using a visual analogue scale and a pain score of > or =5 was treated with intravenous morphine sulfate. Patients were discharged home on oral oxycodone.', 'The total doses of fentanyl administered during surgery were higher in the placebo group compared to the DM group (4.1 +/- 2 vs 2.6 +/- 1.4 microg/kg, P = 0.02) and the total doses of intravenous morphine administered in the postoperative period were also higher in the placebo group compared to the DM group (150 +/- 80 vs 73 +/- 56 microg/kg, P = 0.004). The placebo group had a higher pain score at the time of admission to the Day Surgery Unit (DSU) and a higher maximum pain score, compared to the DM group, during their combined stay in the Post-Anesthesia Care Unit and DSU (7.3 +/- 1.5 vs 3.1 +/- 2.6, P = 0.001).'] Does oral dextromethorphan reduce perioperative analgesic administration in children undergoing tympanomastoid surgery?