Adverse drug reactions occur at a high rate in hospitalized children, frequently due to antiepileptic drug administration. Phenytoin is a commonly used drug, and its metabolism is mediated by a specific cytochrome-P450 isoform, CYP2C9, which is encoded by a polymorphic gene. It is worth noting that very frequently administered drugs, such as proton pump inhibitors, compete with phenytoin for CYP2C19-mediated metabolism. Here we describe a case of phenytoin intoxication in a child with defective CYP2C9, after omeprazole administration.
Phenytoin Adverse drug reactions Omeprazole CYP2C9 CYP2C19
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Compliance with ethical standards
Conflict of interest
Informed consent was given by the patient’s legal guardians for the publication of this study.
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