著者
細野 智美 近藤 愛子 神林 泰行 本間 真人
出版者
公益社団法人 日本薬学会
雑誌
YAKUGAKU ZASSHI (ISSN:00316903)
巻号頁・発行日
vol.137, no.8, pp.999-1003, 2017 (Released:2017-08-01)
参考文献数
12
被引用文献数
1

Several case studies have reported a possible drug interaction between warfarin and tramadol where tramadol coadministration enhanced the antithrombotic effects of warfarin. To assess this drug interaction, changes in prothrombin time-international normalized ratio (PT-INR) before and after tramadol coadministration were investigated in patients receiving warfarin. For this study, we examined 54 patients (male/female: 22/32, 68.4±12.7 years) who were being treated with warfarin for deep vein thrombosis, atrial fibrillation, arteriosclerosis obliterans, congestive heart failure, and other vascular diseases. Significant increases in PT-INR were observed 9.5 (1-118) d after coadministration of tramadol (1.81±0.56 vs. 2.47±1.10, p<0.01). Twenty-eight patients (PT-INR increased group) with PT-INR elevation of greater than 0.5 or dose reduction of warfarin after coadministration of tramadol were compared with other groups of patients to find drug interaction risk factors. Logistic regression analysis revealed that lower levels of albumin (3.5 g/dL or less) [odds ratio (OR) 22.1; 95%CI 2.9-169.9]; lower eGFR (50 mL/min or less) (OR 7.7; 95%CI 1.4-42.0); and PT-INR before tramadol coadministration (OR 38.2; 95%CI 3.7-397.6) were characteristic of the PT-INR increased group. These results suggest that tramadol coadministration enhanced the antithrombotic effects of warfarin in patients with higher PT-INR, lower albumin levels and decreased renal function as the risk factors for this drug interaction.
著者
塚本 晶子 本間 真人 神林 泰行 木津 純子 幸田 幸直
出版者
一般社団法人日本医療薬学会
雑誌
医療薬学 (ISSN:1346342X)
巻号頁・発行日
vol.33, no.8, pp.687-692, 2007 (Released:2009-09-04)
参考文献数
16
被引用文献数
5 4

One of the major adverse effects of Shakuyaku-kanzo-To (SKT),a herbal medicine containing licorice,is licoriceinduced pseudoaldosteronism with hypokalemia and hypertension.Owing to the risk of hypokalemia,caution should be therefore exercised when SKT is co-administered with potassium lowering drugs.In order to clarify this risk,we examined the occurrence of hypokalemia in 103 patients receiving SKT.Thirty (29.1%) of the 103 patients developed hypokalemia and SKT dosing periods tended to be longer in these patients than in those who did not develop hypokalemia (54.5 vs.23.0 days,respectively).The co-administration of potassium lowering drugs was more frequent in the patients with hypokalemia (90.0% vs.64.4% for no hypokalemia p<0.01).The occurrence rates of hypokalemia varied with drugs co-administered with SKT ; with 75.0% for glycyrrhizin preparations,47.2% for diuretics,41.9% for glucocorticoids,20.0% for sennoside preparations and 25.0% for others.The above results confirmed that the co-administration of potassium lowering drugs enhanced SKT-induced hypokalemia.Frequent serum potassium monitoring is therefore required when potassium lowering drugs,especially glycyrrhizin preparations,diuretics and glucocorticoids,are co-administered to patients receiving SKT.