The hepatic and renal mechanisms of drug interactions with cimetidine.

Cimetidine is one of the most frequently prescribed drugs with a known potential to interfere with the metabolic disposition of numerous other medications. Some of these drug interactions may be hazardous to patients. The hepatic and renal mechanisms of drug interactions with cimetidine are discussed in this article. The interactive processes include inhibition of hepatic microsomal enzyme activity, reduction of liver blood flow, and competition for renal tubular secretory sites. The clinical significance and proposed mechanisms of interaction for individual drugs are also presented.