Symptoms and danger signs in acute drug hypersensitivity.

Early and rapid recognition of severe adverse drug reactions is essential. Prompt withdrawal of the offending drug is the most important action to minimize morbidity and mortality. Dependent on the type of reaction, e.g. in immediate type reactions instant withdrawal and therapy are mandatory, whereas in delayed reactions diagnosis as early as possible may be life-saving. The skin is an important herald organ and may early signal a severe evolution of a cutaneous reaction or involvement of circulating blood cells or internal organs. A synthesis considering all factors should be made to obtain an early and correct diagnosis.