ABSTRACT
The interaction is a consequence of the displacement of warfarin from plasma albumin by the antiiflammatories. Since many patients receive vasoactive drugs, an interaction due to changes in blood flow is possible. The barbiturates are very potent inducers and have often been implicated in drug interactions. Plasma-binding displacement of the anticoagulant also contributes to this interaction. The interaction occurs especially in patients who are genetically slow acetylators of isoniazid, and therefore have elevated levels of the drug. Serious interactions have also occurred when patients on monoamine oxidase-inhibitor therapy ingested cheese of high tyramine content. Scientists are becoming aware of the potential interactions between tobacco smoke and drugs in man. Changes in electrolyte or fluid balance may lead to severe toxic interactions. Clinically significant effects have occurred only in a minority of patients who have ingested potentially interacting drugs.
