Drug-drug interactions with antirheumatic agents: review of selected clinically important interactions.

Drug therapy for rheumatoid arthritis (RA) often requires the use of more than one drug, thus drug-drug interactions are very likely in this patient population. We discuss the pharmacokinetic and pharmacodynamic mechanisms involved in drug-drug interactions. Our review focuses on selected examples involving drugs used to treat RA and other antirheumatic drugs [e.g., methotrexate and nonsteroidal antiinflammatory drugs (NSAID)] or with other therapeutic classes of drugs (e.g., NSAID and warfarin). Studies and case reports of drug-drug interactions with antirheumatic drugs are critically evaluated and the potential clinical implications are discussed.