The Comparative Influence of Prophylactic Antibiotics on the Prothrombin Response to Warfarin in the Postoperative Prosthetic Cardiac Valve Patient Cefamandole, Cefazolin, Vancomycin

Abstract

A prospective randomized trial was conducted comparing the effect of three antibiotics: cefamandole (CM), cefazolin (CZ), and vancomycin (V), used as prophylaxis for prosthetic valve surgery, on the prothrombin (PT) response to warfarin (W) on the third day of anticoagulant therapy. Twenty patients, with normal preoperative PTs, were randomized to each antibiotic. Their PTs were not significantly different at 2 hours after operation and the morning before W was begun. The three groups received similar W doses for 2 days, and the PT, as percentage of activity, on the morning of the third day demonstrated that V (51 +/- 18%) was significantly greater (p less than 0.005) than CM (29 +/- 14%) or CZ (38 +/- 18%). CM had a significantly greater percentage of change in PT (64 +/- 14%, p less than 0.0001) from the first to third day than either CZ (51.1 +/- 18%) or V (44.6 +/- 19%). CM also had a greater number of patients (6) with PTs greater than or equal to 30 seconds on day 3 than either CZ (1) or V (1). The antibiotic influence on the PT response to W in this study is ranked as CM greater than CZ greater than V.

The Association Between Cephalosporin and Hypoprothrombinemia: A Systematic Review and Meta-Analysis

“…The remaining 15 studies were included in the final meta-analysis. They were five RCTs [12,13,14,15,16], four prospective cohort studies [17,18,19,20], five retrospective cohort studies [21,22,23,24,25], and one case-control study [26], published between 1984 and 2016. A total of five NMTT-cephalosporins were included in the analysis; cefamandole [13,23,24], cefoperazone [20,22,25,26], cefotetan [15,16,18,19,20], cefmetazole [26], and moxalactam [12,14,17,21,22,24].…”

Amoxicillin/clavulanic acid‐warfarin drug interaction: a randomized controlled trial

“…the N-methyl-thio-tetrazole (NMTT) group and beta-lactam antibiotics, have been reported to interact with warfarin [1,2]. Amoxicillin/clavulanic acid (amoxiclav), a member of the penicillin class, also has been suggested to potentiate the effects of warfarin [3].…”

A Possible Interaction of Voriconazole and Warfarin in a Renal Transplant Recipient

“…Other drugs known to potentiate warfarin were given prior to and during voriconazole therapy including acetaminophen, pantoprazole, levofloxacin, methylprednisolone and vancomycin [4,5,11,17,18]. The relationship between levofloxacin and elevated INR in patients taking warfarin is controversial.…”