title: Timing of expression of blood coagulation abnormality in patients treated with warfarin and s-1 concomitantly.
abstract: Although S-1 is frequently used in cancer chemotherapy, the drug interaction with warfarin, an anticoagulant agent, is not fully paid attention. In the present study, we investigated retrospectively the timing of expression of blood coagulation abnormality in nine patients treated with warfarin and S-1 concomitantly. In five patients, the dose of warfarin was reduced or interrupted after concomitant use of S-1. The International Normalized Ratio (INR) was significantly increased after combination with S-1 compared with the former value. In all patients, the INR was increased in three weeks after combination with S-1. On the other hand, serum creatinine, aspartate aminotransferase, alanine aminotransferase or serum albumin was not different before and after combination with S-1. These results suggest that the careful monitoring of the blood coagulation ability is necessary in all patients receiving warfarin and S-1 concomitantly.
authors.affiliation: Department of Pharmacy, Kyushu University Hospital, Maidashi, Higashi-ku, Fukuoka, Japan. yamada-t@pharm.med.kyushu-u.ac.jp
authors.forename: Takaaki
authors.initials: T
authors.lastname: Yamada
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Watanabe
authors.forename: Takahisa
authors.initials: T
authors.lastname: Yano
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Nonaka
authors.forename: Atsushi
authors.initials: A
authors.lastname: Takada
authors.forename: Masanobu
authors.initials: M
authors.lastname: Sonoda
authors.forename: Toshio
authors.initials: T
authors.lastname: Kubota
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Egashira
authors.forename: Ryozo
authors.initials: R
authors.lastname: Oishi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000008:administration & dosage* / Q000009:adverse effects*; D001778:Blood Coagulation Disorders / Q000139:chemically induced*; D004338:Drug Combinations; D004347:Drug Interactions; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D019934:International Normalized Ratio; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D010094:Oxonic Acid / Q000008:administration & dosage* / Q000009:adverse effects*; D012189:Retrospective Studies; D005641:Tegafur / Q000008:administration & dosage* / Q000009:adverse effects*; D013997:Time Factors; D014859:Warfarin / Q000008:administration & dosage* / Q000009:adverse effects*
chemical_list: D000925:Anticoagulants; D004338:Drug Combinations; C079198:S 1 (combination); D005641:Tegafur; D014859:Warfarin; D010094:Oxonic Acid