Adverse Drug Reactions in Adults Leading to Emergency Department Visits

Background: Medication-related visits to the emergency department are an important but poorly understood phenomenon. A large number of adverse drug event-related visits and admissions are preventable which highlights the importance of public education on the proper use of drugs. Methodology: A prospective observational study was conducted including selected adults presenting to the emergency department over a period of 1 year. Drug-related visits were assessed by two physicians. Discrepancies were adjudicated by two independent reviewers. Results: Among the 133 patients included in the study, the emergency department visit was identified as drug-related adverse reactions for 50 patients (37.59%); of these 9 visits (18%) were deemed preventable. Severity was classified as mild in 14%, moderate in 68% and severe in 18%. The most common Adverse drug reactions (ADR) were neuropsychiatric events (n=10 [28.57%]), gastrointestinal reactions (n=13 [37.14%]) and angioedema (n=4[11.42%]). The most common drug classes involved were NSAID (n=16 [32%]), Glucocorticoids (n=10 [20%]), Fluoroquinolones (n=4 [8%]) and Insulin (n=8 [16%]). The factors associated with Adverse drug reaction related visits to the emergency department found in this study were the number of co morbidities a patient has, total number of pharmacy visits, total number of physicians prescribers and total number of medications a patient takes at a given period. A patient having one or more co morbidities (p-value 0.0002) has a more chance of developing an ADR. A patient going to more than one physician (p value 0.0124) and pharmacy (p value 0.0002) along with a daily intake of more than two medications (p value <0.0001) has a greater chance of developing an ADR. Another observation made during this study is that patients usually make multiple visits to the local pharmacy with the same prescription and get the drugs over the counter. Discussion: A high proportion of preventable adverse drug events were around a small number of drugs. Effective safety practices directed to reduce the incidence of medication errors are needed. 45% (n=72) of Adverse drug events were detected at the Emergency Department and 55% (n = 88) were detected during hospitalization. 62.3% of Adverse drug events were considered potentially avoidable (n = 109). 38.1% of adverse drug events were serious, 40.0% moderate and 21.9% mild. Drugs most commonly involved in the Adverse drug events sample studied included: antimicrobials (24.0%), systemic corticoids (15.4%), NSAIDs (11.4%), diuretics (10.3%), digoxin (9.1%), insulin and oral hypoglycemic agents (5.7%), anticoagulants and heparin (5.7%) Elderly age group patients are at high risk of developing drug related adverse effects because of increased sensitivity to the unintended side effects or adverse drug reactions of medications that could result from incorrect dosing, and their use of more medications. Because of the increasing number of drugs, regimen complexity, continuously changing drug interactions and adverse effects, physician memory can no longer serve as a reliable bridge between research advances and clinical practice. We must remember that “there are no biologically safe drugs; there are only safe physicians” Most studies reviewed above, suggest that a significant percentage of Adverse drug events and drug related problems (DRPs) are preventable. Conclusion: More than 1 in 100 emergency department visits are due to drug-related adverse events, a potentially preventable problem in our health care system. Patients prescribed with more than 2 drugs and going to more than one pharmacy and physician for treatment have higher risk for developing adverse drug reactions. Physicians should prescribe NSAIDS and glucocorticoids with caution to patients along with adequate counseling regarding their adverse drug reactions. Keywords: Adverse drug reaction, Emergency room, Drug related problems