Prevalence and Therapeutic Classifications of FDA-Approved Prescription Drugs With Boxed Warnings

Purpose: To characterize and determine the prevalence of drugs with boxed warnings (BXWs) based on a review of structured product labels (SPLs) available on the National Library of Medicine (NLM) DailyMed website. Methods: A cross-sectional review was conducted of SPLs with BXWs for human prescription drugs on the NLM DailyMed website in July 2012. The presence of a BXW in the DailyMed version of the SPL was validated by cross-referencing a corresponding label on the FDA website. The SPLs were organized into drug groups, and descriptive statistics were used to determine the proportion of SPLs and drug groups associated with a validated BXW. The top therapeutic classes of drugs with BXWs were determined as well as the percentage of the top 100 BXW-associated drugs used in US hospitals and retail settings in 2012. Results: Findings revealed that 35% (n = 4940/14,264) of drug labels on DailyMed and 35% (n = 650/1848) of the drug groups created were associated with a validated BXW. Central nervous system agents, antineoplastic agents, and cardiovascular drugs were the most common therapeutic classes. In 2012, 39% of the top 100 drugs were associated with a BXW.