Drug Incompatibility in Emergency Departments: A Comparative Evaluation of Clinical Practices and Pharmaceutical Interaction Sources

Objective Intravenous (IV) drug incompatibility represents a significant patient safety concern in emergency departments, where multiple medications are frequently administered under time pressure. This study aimed to evaluate physicians’ real-world IV drug mixing practices and to assess the consistency of major IV compatibility databases with these practices. Material and Methods This nationwide, cross-sectional study was conducted using an anonymous online survey distributed to emergency department physicians across Türkiye. The survey collected data on drugs commonly mixed in clinical practice, drugs perceived as compatible, and information sources used for compatibility checks. All reported drug combinations were evaluated using four major IV compatibility databases. Analyses were limited to descriptive statistics and are presented as frequencies and percentages. Results A total of 34 physicians participated in the study. Clinical experience was the most frequently used source for assessing IV drug compatibility (n = 30, 88.2%). Significant discrepancies were observed between clinical practice and database information. Several commonly mixed drugs had no compatibility data available in any of the databases. Among evaluated combinations, some were classified inconsistently across sources, being reported as compatible, incompatible, or uncertain depending on the database. Overall, substantial gaps and inconsistencies in IV compatibility information were identified. Conclusion Emergency physicians predominantly rely on informal knowledge when mixing IV drugs, while available compatibility databases demonstrate notable data gaps and inter-database inconsistencies. These findings highlight the need for improved clinician education, expansion of compatibility database content—particularly for commonly used agents—and the development of practical decision-support tools to enhance medication safety in emergency settings.