[Drug allergy]

Drug reactions can be differentiated into immediate and delayed types. Immediate type reactions are life threatening or manifest themselves as urticaria /angioedema, asthma or anaphylaxis. They may be mediated by specific IgE antibodies or more frequently by non-immunological mechanisms (so-called "pseudoallergies"). Delayed type reactions are the most frequent immunological reactions. They appear mostly as maculo-papulous exanthema. Rarely they may become life threatening and lead to fever and involvement of visceral organs. In life threatening reactions further exposure to the causative drug should be strictly avoided. If the diagnosis of a drug allergy and of the causative drug is insecure, further allergological investigations are justified.