PT  - JOURNAL ARTICLE
AU  - Peter J. Zed, PharmD
AU  - Riyad B. Abu-Laban, MD MHSc
AU  - Robert M. Balen, PharmD
AU  - Peter S. Loewen, PharmD
AU  - Corinne M. Hohl MD
AU  - Jeffrey R. Brubacher, MD MSc
AU  - Kerry Wilbur, PharmD
AU  - Matthew O. Wiens, BSc(Pharm)
AU  - Leslie J. Samoy, BSc(Pharm)
AU  - Katie Lacaria, BSc(Pharm)
AU  - Roy A. Purssell MD
TI  - Incidence, severity and preventability of medication-related visits to the emergency department: a prospective study
AID  - 10.1503/cmaj.071594
DP  - 2008 Jun 03
TA  - Canadian Medical Association Journal
PG  - 1563--1569
VI  - 178
IP  - 12
4099  - http://www.cmaj.ca/content/178/12/1563.short
4100  - http://www.cmaj.ca/content/178/12/1563.full
SO  - CMAJ2008 Jun 03; 178
AB  - Background: Medication-related visits to the emergency department are an important but poorly understood phenomenon. We sought to evaluate the frequency, severity and preventability of drug-related visits to the emergency department. Methods: We performed a prospective observational study of randomly selected adults presenting to the emergency department over a 12-week period. Emergency department visits were identified as drug-related on the basis of assessment by a pharmacist research assistant and an emergency physician; discrepancies were adjudicated by 2 independent reviewers. Results: Among the 1017 patients included in the study, the emergency department visit was identified as drug-related for 122 patients (12.0%, 95% confidence interval [CI] 10.1%–14.2%); of these, 83 visits (68.0%, 95% CI 59.0%–76.2%) were deemed preventable. Severity was classified as mild in 15.6% of the 122 cases, moderate in 74.6% and severe in 9.8%. The most common reasons for drug-related visits were adverse drug reactions (39.3%), nonadherence (27.9%) and use of the wrong or suboptimal drug (11.5%). The probability of admission was significantly higher among patients who had a drug-related visit than among those whose visit was not drug-related (OR 2.18, 95% CI 1.46–3.27, p < 0.001), and among those admitted, the median length of stay was longer (8.0 [interquartile range 23.5] v. 5.5 [interquartile range 10.0] days, p = 0.06). Interpretation: More than 1 in 9 emergency department visits are due to drug-related adverse events, a potentially preventable problem in our health care system.