Table 1: Scoring of clinical severity of herb-warfarin interaction [14].

Clinical severityPotentiation Inhibition

Major Death, major bleeding, entailing entire cease of warfarin therapyOccurrence of thrombosis

Moderate INR increase, entailing adjustment in warfarin dosage
INR increase to greater than 5.0
INR increase by greater than 1.5 units
INR decrease, entailing adjustment in warfarin dosage;
INR decrease to less than 1.5
INR decrease by greater than 1.5 units

Minor INR increase but requiring no change in warfarin dosage
INR increase to no more than 5.0
INR increase by smaller than 1.5 units
INR decrease but requiring no change in warfarin dosage
INR decrease to no more than 1.5
INR decrease by smaller than 1.5 units

Nonclinical No change in INRNo change in INR