Cardiac dysrhythmias are common in acute intoxications. However, epidemiological data is rare and restricted to specific substances. From 1995 to 2003 (until September) 91 285 inquiries of physicians and paramedics to a poison center regarding acute intoxications were analyzed revealing 9888 patients (10.8%) suffering from disturbances of the cardiac rhythm. In a first step of the explorative data analysis dysrhythmias were graduated into three categories (I: tachycardia/bradycardia; II: arrhythmia/conduction disorder; III: ventricular dysrhythmia/cardiac arrest) and the frequencies of the involved substances were determined. In a second step substances which resulted to be of significant interest were investigated for their specific pattern of dysrhythmias. For category I (n = 8730) predominantly tricyclic antidepressants, neuroleptics, benzodiazepines, betablockers, and nonsteroidal antiinflammatory drugs were registered (II: [n = 949] tricyclic antidepressants, digitalis glycosides, benzodiazepines, neuroleptics, Ca antagonists; III: [n = 209] tricyclic antidepressants, neuroleptics, sotalol, ethanol, central nervous system stimulants). Tricyclic antidepressants resulted in 23.4% of the reported cases in symptoms of category I (II: 2.3%, III: 0.6%; n = 8535). The highest rates of dysrhythmias were observed for sotalol (I: 34.7%, II: 21.6%, III: 8.0%; n = 176) as compared to the lowest rates found for paracetamol (I: 5.2%, II: 0.3%, III: 0.1%; n = 6429). The present investigation provided a comprehensive clinical overview about the frequency of dysrhythmias and involved substances during acute poisonings in emergency medicine. Furthermore, the specific effects of selected substances concerning dysrhythmias could be determined in view of a clinical database.