Fig. 1From: A case of a warfarinized renal cancer patient monitored for prothrombin time-international normalized ratio during methadone introductionTransition of oral oxycodone equivalent narcotic dose, warfarin dose, and PT-INR. Horizontal axis: number of days elapsed since hospitalization (days). Figure top: transition of oral oxycodone equivalent narcotic dose. Vertical axis: oral oxycodone equivalent narcotic dose (mg). Figure bottom: transition of warfarin dose and PT-INR. Vertical axis: warfarin dose (mg) and PT-INR. a The peak of PT-INR after administration of acetaminophen. b The peak of PT-INR after administration of oxycodone. c The plateau of PT-INR after administration of methadone. Methadone was not converted to form a ratio with other opioids; the graph was prepared by converting methadone 15 mg to oral oxycodone 80 mg [13]Back to article page