[Skip to Content]
[Skip to Content Landing]
Primer on Allergic and Immunologic Diseases
November 26, 1982

Allergic Reactions to Drugs and Biologic Agents

JAMA. 1982;248(20):2637-2645. doi:10.1001/jama.1982.03330200061015

ADVERSE reactions to drugs are common clinical problems and a significant source of morbidity and mortality. The true prevalence is difficult to determine, but estimates of drugrelated complications have ranged from 6% to 15% of hospitalized patients. A variety of mechanisms, presumably unrelated to hypersensitivity, account for the majority of these reactions (Table 6-1). Actual allergic or immunologic drug reactions likely account for 25% or less of the overall number of adverse drug reactions (Table 6-2).

A minority of adverse drug reactions, perhaps 6% to 10%, are secondary to or closely associated with immunologic mechanisms (Table 6-2). The classification (as listed in Tables 6-1 and 6-2) is arbitrary. Many of the mediators of hypersensitivity are involved in the host's response to toxic injury. It is often difficult to tell if a condition represents a primary hypersensitivity reaction or a response to another form of organ damage.

An understanding of the