Why the study?
Does ciprofloxacin 500 mg twice daily increase INR or bleeding risk in patients stabilized on long-term warfarin therapy?
Does ciprofloxacin 500 mg twice daily increase INR or bleeding risk in patients stabilized on long-term warfarin therapy?
Short-term ciprofloxacin therapy (500 mg twice daily for 10 days) does not appear to significantly interact with warfarin or increase bleeding risk in stabilized patients.
Supports short-term ciprofloxacin in stable warfarin patients without INR adjustment; confirms no clinically relevant interaction in this RCT.
This study prospectively evaluated the potential interaction between the oral anticoagulant warfarin and the quinolone antimicrobial agent ciprofloxacin. After a 10-day placebo lead-in phase, 16 patients stabilized with long-term warfarin therapy were randomized to receive ciprofloxacin 500 mg or a matching placebo twice/day for 10 days. International normalized ratios (INRs) measured by both standard laboratory analysis and by Coumatrak (finger-stick) methods were evaluated at 3- to 5-day intervals. No patient experienced a significant increase in INR. No patient experienced a bleeding event. These data support the fact that a warfarin-ciprofloxacin interaction does not routinely occur at this dosage and duration of ciprofloxacin therapy.
No takes yet. Share an insight, caveat, or question.
Bianco et al. (1992) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: