THE INFLUENCE OF BARBITURATES ON COUMARIN PLASMA LEVELS AND PROTHROMBIN RESPONSE*

Abstract
Results obtained in guinea pig, dog and man show that pretreatment with barbiturates may antagonize the hypoprothrombinemic effect of coumarin anticoagulants. This effect has been correlated with lower plasma levels of the anticoagulant drugs. In man, route and timing of dosage significantly influence this barbiturate effect.