Drug-related emergency department visits and hospital admissions.

The incidence and causes of drug-related hospital admissions and visits to an emergency department were evaluated. A retrospective chart review was conducted to identify drug-related visits and admissions for all patients who visited the emergency department of a 517-bed tertiary-care institution during a four-month period. Drug-related illnesses were classified as adverse drug reaction (ADR), overdose or abuse, noncompliance, drug interaction, or toxicity. Patient data included demographic characteristics, medication history, serum drug concentrations, length of hospital stay, and hospital admission charges. Of 10,184 patients who visited the emergency department, 293 (2.9%) had drug-related illnesses; 71 (24%) of these patients were admitted. The drug classes most commonly involved were drugs of abuse (23.2%), anticonvulsants (17.1%), antibiotics (12.6%), respiratory drugs (8.9%), and pain medications (8.9%). The most common category of drug-related illness was overdose or abuse (35%) followed by noncompliance (28%), ADR (28%), toxicity (8%), and drug interaction (1%). The average length of stay for patients who were admitted was 5.8 days, and the average cost of admission was $8888. Drug-related illnesses accounted for 2.9% of hospital admissions and visits for patients in the emergency department. The most commonly identified drug-related illnesses were overdose or abuse, noncompliance, and ADRs; the drug classes most commonly implicated were drugs of abuse, anticonvulsants, and antibiotics.