Potential Cytochrome P450 Drug-Drug Interactions among Pediatric Patients Undergoing Tonsillectomy:

ObjectiveTo evaluate the frequency of potential cytochrome P450 (CYP) drug-drug interactions affecting opioid metabolism among children undergoing adenotonsillectomy.Study DesignCase series with chart review.SettingTertiary care children’s hospital.Subjects and MethodsA retrospective review was conducted of 1000 patients undergoing adenotonsillectomy at Children’s Hospital of Wisconsin. The discharge medication reconciliation form was reviewed. Each patient’s list of medications was compared with various published sources to determine whether medications causing CYP inhibition or induction were present.ResultsThere were 157 unique medications with systemic absorption given postoperatively to this patient cohort. Eight percent of patients were on at least 5 medications after surgery other than their posttonsillectomy medication. The 5 most commonly prescribed medications were albuterol, cetirizine, fluticasone nasal spray, montelukast, and polyethylene glycol. Per a list of known CYP inducers and inhibitor...