Epidemiology and causes of drug hypersensitivity

Abstract

Drug hypersensitivity reactions (DHRs) are the adverse ef-fects of drugs, taken at a dose which is tolerated by normal subjects, which clinically resemble allergy. There are few true epidemiological data on DHRs. The available informa-tion requires a cautious interpretation because the patho-genic mechanism has not been demonstrated by diagnos-tic tests. Both under-and over-diagnosis must be taken into account. DHRs may represent up to one third of adverse drug reactions, be life-threatening, require or prolong hos-pitalization, and entail changes in drug prescription. They concern more than 7% of the general population, and therefore are an important public health problem. A few risk factors have been pinpointed. Future progress in genetics, as well as well-designed epidemiological studies on hyper-sensitivity drug reactions, will be helpful in identifying pa-tients at risk of developing such reactions, in particular se-vere ones, and in implementing early preventive measures. This review describes current data on the incidence, preva-lence, mortality, and risk factors of these reactions. © 2007 by S. Karger AG, Basel. All rights reserved.