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Prevention of adverse drug events in hospitals

Junya Zhu, PhD, MS, MA
Saul N Weingart, MD, PhD
Section Editor
Andrew D Auerbach, MD, MPH
Deputy Editor
Judith A Melin, MA, MD, FACP


Adverse drug events (ADEs) comprise the largest single category of adverse events experienced by hospitalized patients, accounting for about 19 percent of all injuries [1]. The occurrence of ADEs is associated with increased morbidity and mortality [2,3], prolonged hospitalizations [4], and higher costs of care [2,5].

A 2007 report from the Institute of Medicine estimated that between 380,000 and 450,000 preventable ADEs occurred annually in United States (US) hospitals [6]. Assuming 400,000 preventable ADEs each year at an incremental hospital cost of $5857 each [5], the estimated cost of ADEs in 2006 was 3.5 billion US dollars [6]. The Joint Commission has established national patient safety goals requiring each health care organization to implement comprehensive medication reconciliation at every transition point (eg, admission, transfer, discharge) along the continuum of care [7].

This topic will focus on interventions to prevent ADEs caused by medication errors in the hospital setting. Specific issues related to hospital discharge, drug prescribing in older adults, and adverse drug reactions (ADRs) are discussed in detail elsewhere. (See "Hospital discharge and readmission" and "Drug prescribing for older adults" and "Drug allergy: Classification and clinical features", section on 'Categories of adverse drug reactions'.)


Adverse drug events (ADEs) are defined as any injuries resulting from medication use, including physical harm, mental harm, or loss of function [8]. ADEs, compared with medication errors, are a more direct measure of patient harm.

Medication errors refer to any mistakes occurring in the medication use process, regardless of whether an injury occurred or whether the potential for injury was present [8,9]. Approximately 1 in 100 medication errors result in an ADE, while 7 in 100 have the potential to do so [10]. Although relatively few medication errors result in ADEs, they provide important information for identifying opportunities to improve patient care.

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Literature review current through: Oct 2017. | This topic last updated: Oct 19, 2017.
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