[ Drug allergies: clinical presentation and red flags].

In theory, all medicines can elicit allergic reactions. However, there are large differences in the frequency and clinical presentation of these reactions. Antibiotics, antiepileptic agents and NSADs trigger allergic reactions most frequently. The risk of drug allergy and of a complicated clinical course depends on the individual degree of immune activation, the dose, duration of treatment, route of administration, patient sex as well as HLA-traits, which are increasingly being identified. This article presents the commonest types of immune-mediated drug-related hypersensitivity reactions and discusses red flags which are associated with a complicated clinical course.