Medication safety represents an important challenge in children. There are limited studies on medication errors in pediatric patients visiting emergency departments. To help bridge this gap, we characterized the medication errors detected in these patients, determining their severity, the stages of the medication process in which they occurred, the drugs involved, and the types and causes associated with the errors. We conducted a multicenter prospective observational study in the pediatric emergency departments of 8 Spanish public hospitals over a 4-month period. Medication errors detected by emergency pediatricians in patients between 0 and 16 years of age were evaluated by a clinical pharmacist and a pediatrician. Each medication error was analyzed according to the updated Spanish Taxonomy of Medication Errors. In 99,797 visits to pediatric emergency departments, 218 (0.2%) medication errors were detected, of which 74 (33.9%) resulted in harm (adverse drug events). Preschoolers were the age group with the most medication errors (126/218). Errors originated mainly in the prescribing stage (66.1%), and also by self-medication (16.5%) and due to wrong administration of the medication by family members (15.6%). Dosing errors (51.4%) and wrong/improper drugs (46.8%) were the most frequent error types. Anti-infective drugs (63.5%) were the most common drugs implicated in medication errors with harm. Underlying causes associated with a higher proportion of medication errors were "medication knowledge deficit" (63.8%), "deviation from procedures/guidelines" (48.6%) and "lack of patient information" (30.3%). Medication errors presented by children attending emergency departments arise from prescriptions, self-medicationand administration, and lead to patient harm in one third of cases. Developing effective interventions based on the types of errors and the underlying causes identified will improve patient safety.

Despite the progressive increase in obesity and associated chronic diseases in children, there is limited evidence on the optimal dosage of most medications for obese children and adolescents. This review analyzes the influence of pathophysiological changes on pharmacokinetics and pharmacodynamics and evaluates the body size descriptors used in clinical practice. Patients with obesity present significant pathophysiological alterations, such as a substantial increase in fat/lean mass ratio, increased blood flow and cardiac output, and changes in plasma protein binding, which may affect the volume of distribution of drugs and the adjustment of the loading dose. In these patients, the distribution volume of hydrophilic drugs appears to slightly increase, while it varies widely—depending on the drug and other factors such as affinity for other tissues—for lipophilic drugs. On the other hand, a reduction in tissue perfusion, alterations to liver enzyme activity, and an increase in liver and kidney mass and blood flow have been reported, indicating a possible modification in drug clearance and necessitating adjustments to maintenance regimens. Furthermore, while there are multiple size descriptors, it is difficult to establish a single dosing strategy for the obese population, given the lack of studies confirming the extent of changes in pharmacokinetic processes, which will also depend on the properties of each drug, such as liposolubility and elimination pathways. New strategies need to be developed to characterize pharmacokinetic and pharmacodynamic changes in the obese pediatric population in order to optimize dosing regimens and improve the safety and efficacy of treatments.

Pediatric patients are more likely to experience medication-related errors and serious associated harms. The identification of high-risk medications (HRM) and their study in special populations, such as children with excess body weight (EBW), is a part of safety improvement strategies. To generate, through a consensus technique structured by an interdisciplinary group of pediatricians and hospital pharmacists, an operational and updated list of HRM for hospital use in children over 2 years of age. The document was part of a collaboration project between the Spanish Society of Hospital Pharmacists and the Spanish Society of Pediatric Hospital Medicine. The study was carried out in 2 sequential phases: (a) preparation of a preliminary list of HRM through bibliographic review and (b) subsequent application of the double-round Delphi method to agree on a definitive list of HRM. The results obtained were validated by calculating the probability of chance agreement and the modified Kappa statistic for each drug. The original list obtained by bibliographic review included 26 pharmacological classes and 96 drugs. Of the total of 37 experts, 32 (86.4%) completed both rounds of the Delphi. The final consensus list of HRM incorporated 24 pharmacological classes and 101 drugs. The modified Kappa statistic reflected a high percent agreement (94.9%) in the consensus reached by the participants. This list can establish a tool for future studies and interventions to improve the safety of medications in general pediatric population, as well as in high-risk subgroups, such as pediatric patients with EBW.