Key result
The addition of ciprofloxacin to a stable warfarin regimen in a 77-year-old man resulted in an INR elevation to 5.1 and a fatal intracerebral hemorrhage within six days.
Why the study?
Does ciprofloxacin increase the risk of bleeding and elevate INR in patients taking warfarin?
Case Report (n=1)
Does ciprofloxacin increase the risk of bleeding and elevate INR in patients taking warfarin?
This case report highlights a potentially fatal interaction between warfarin and ciprofloxacin, emphasizing the need for close INR monitoring when co-administering these medications.
Case suggests possible fatal interaction; leaves open whether ciprofloxacin routinely elevates INR or bleeding risk with warfarin.
Warfarin is a potent anticoagulant that acts by interfering with hepatic synthesis of vitamin Kdependent clotting factors (II, VII, IX, and X).I,2 Bleeding is the primary complication of warfarin therapy.3 A variety of drugs, including many antimicrobial agents, can increase the anticoagulant effect of warfarin. 2 ,4 Ciprofloxacin is one antibiotic reported to influence the effect of warfarin. s -1o
No takes yet. Share an insight, caveat, or question.
Byrd et al. (1999) conducted a case report in Atrial fibrillation on warfarin therapy (n=1). Ciprofloxacin vs. Stable warfarin therapy alone (prior to ciprofloxacin) was evaluated on Prothrombin time/INR elevation and bleeding event. The addition of ciprofloxacin to a stable warfarin regimen in a 77-year-old man resulted in an INR elevation to 5.1 and a fatal intracerebral hemorrhage within six days.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: