Adverse Drug Event-Related Admissions to a Pediatric Emergency Unit.

OBJECTIVES: The objectives of this study were to analyze adverse drug events (ADEs) related to admissions to a pediatric emergency unit and to identify the associated risk factors. METHODS: This was a prospective study. Demographic data and details of medications were collected for each patient admitted. Case studies were performed by clinical pharmacists and the clinical team to discuss whether the admission was due to an ADE and to characterize the ADE. Multivariate logistic regression was used for statistical analysis. RESULTS: In total, 1708 pediatric patients were included in this study. Adverse drug events were the cause of hospital admission in 12.3% of the studied population. The majority of patients presenting with an ADE were in the age group of 0 to 5 years (61.6%), had a mean ± SD age of 4.9 ± 3.9 years, were female (51.2%), were Caucasian (72.0%), and had infectious disorders (49.3%). High frequencies of medication errors (68.8%), use of drugs to treat respiratory disorders (27.7%), and ADEs of mild severity (75.3%) were reported. The risk of being admitted to the pediatric emergency unit for any ADE increased in cases of neurological (odds ratio [OR], 4.63; 95% confidence interval [CI], 2.38-8.99), dermatological (OR, 3.16; 95% CI, 1.93-5.18), and respiratory (OR, 3.02; 95% CI, 1.89-4.83) disorders. CONCLUSIONS: A high frequency of ADE-related admissions to the pediatric emergency unit was observed. The risk of being admitted to the pediatric emergency unit for any ADE increased in cases of neurological, dermatological, and respiratory disorders. Clinical pharmacists play an important role in the identification of ADEs and the education of child caregivers and health care providers concerning pediatric medication.

Drug interaction between phenytoin and valproic acid in a child with refractory epilepsy: a case report.

INTRODUCTION: There are no published reports on pediatric phenytoin toxicity, resulting from the drug interaction between phenytoin and valproic acid. CASE DESCRIPTION: A 12-year-old patient with refractory epilepsy syndrome presented with phenytoin toxicity, following a concomitant treatment with phenytoin, valproic acid, and lamotrigine. The phenytoin concentration detected in the capsules used by the patient was in accordance with the prescribed dose and was appropriate for the age and weight of the patient. However, a supratherapeutic phenytoin serum concentration was observed (21.92 µg phenytoin/mL of blood). Consequently, the phenytoin dose was reduced, and the patient was monitored; 24 hours later the patient did not present with any signs/symptoms of toxicity. DISCUSSION: Despite the appropriate phenytoin concentration in the capsules, the patient presented with phenytoin toxicity. This toxicity likely resulted from the drug interaction between phenytoin and valproic acid that leads to phenytoin displacement from plasmatic proteins and inhibits phenytoin metabolism, thereby increasing the concentration of free drug in the serum.