Case report: ranitidine-induced bradycardia in a patient with dextrocardia.

Although rare, bradycardia and other cardiac arrhythmias have been associated with the use of H2-receptor antagonists. Ranitidine is among the most frequently prescribed drugs. In this article, the authors observed a ranitidine-mediated sinus bradycardia in a man with dextrocardia (situs inversus) who had acute bleeding from a duodenal ulcer. The bradycardia was resolved after ranitidine was discontinued.