Drug Eruptions

Abstract

It would be reasonable to state that any drug may cause a skin rash. The pattern and type of skin rash produced is variable although some drugs are more likely to produce certain types of eruption than others. The mechanism by which drugs produce skin lesions is not fully understood. It seems likely that there are two possible pathogenic pathways, first a direct ‘toxic’ effect on components of the skin, and second ‘allergic’ in which there is an antigen-antibody reaction. In the second type the drug itself may act as the antigen or it may combine with a hapten to form the antigen. Why some individuals develop skin rashes when taking drugs is not known, but host factors are obviously important and the development of rashes appears to be an idiosyncratic response on the part of the individual.