[Adverse drugs reactions: diagnosis and assessment]

Adverse drug reactions (ADR) occur in about 5% of all pharmacologically treated patients. Between 2% and 20% of all hospital admissions are caused by ADR, and approximately 10% of all hospitalized patients experience ADR during their hospital stay. Several thousand patients die due to ADR in Germany each year. ADR-associated drugs come predominantly from the class of non-steroidal antiinflammatory drugs, anticoagulants, acetylsalicylic acid and cardiovascular drugs. Most ADR cases present as gastrointestinal bleeding and adverse cardiovascular effects. Apart from this, one or more drugs are withdrawn from the market each year because of unwanted but mostly rare side effects. In recent years the most prominent cases were rofecoxib, cisapride and cerivastatin. Physicians in Germany are obliged to report ADR. A substantial proportion of ADR, however, is not reported because it is deemed to be either too well known or the association between the drug and the adverse effect is too doubtful. In some cases, histopathological findings are needed to determine the diagnosis of ADR. Accordingly, physicians should inform the pathologist whether an ADR is suspected and which drugs may be responsible.