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November 25, 1992

Allergic Reactions to Drugs and Biological Agents

JAMA. 1992;268(20):2845-2857. doi:10.1001/jama.1992.03490200097011

AN ADVERSE reaction to a drug or a biological agent is an undesirable and usually unanticipated response independent of the intended therapeutic or diagnostic purpose of the medication.1 Although the exact frequency of adverse reactions to drugs and biological agents is unknown, each year approximately 1 to 2 million Americans experience a drug reaction, usually a skin eruption.2 Of all hospitalizations in the United States, 2% to 5% may be due to adverse drug reactions.3 It has been estimated that as many as 30% of hospitalized patients may experience an adverse drug event. A study based on a computerized surveillance system in a 520-bed tertiary care hospital determined that 2% of the 36000 admissions in 1 year were due to adverse drug reactions.3 Of these reactions, 0.2% were severe, life-threatening, and allergic-like (anaphylaxis/anaphylactoid) in nature. In 37665 medical inpatients in Boston, Mass, 23% experienced adverse skin