Some limited, and poor quality evidence suggests that the anticoagulant effects of acenocoumarol and dicoumarol can be increased by oral
chloramphenicol. An isolated report attributes a marked INR rise in a patient taking
warfarin to the use of
chloramphenicol eye drops.
This interaction is by no means adequately established. There would therefore appear to be little reason for avoiding concurrent use, but be aware that increases in INR are possible. The interaction with
chloramphenicol eye drops seems unlikely to be generally relevant.