ABSTRACT
I. INTRODUCTION An adverse reaction to a drug or biological agent is a significant problem in the practice of medicine. An adverse drug reaction is undesirable and usually unanticipated independent of its intended therapeutic or diagnostic purpose. Although the exact frequency of adverse reactions to drugs and biological agents is unknown, it is estimated that each year I to 2 million people in the United States experience a drug reaction. An adverse drug
reaction is reported as the cause of admission in 2% to 5% of all hospitalizations in the United States (1). Also, it is estimated that about 30% of all hospitalized patients experience an adverse drug event (2). The most important form of drug reaction is the immunologically mediated allergic reaction, which is relatively common and occurs unpredictably in an otherwise normal individual. Fear of recurrent allergic reactions often leads to repeated avoidance of a drug of choice. Therefore, measures that prevent, minimize, or reverse allergic reactions to drugs can have a major impact on the effectiveness and cost of patient care (3).
