QUINOLONES AND WARFARIN AND OTHER ORAL ANTICOAGULANTS

The quinolones do not normally alter the effects of coumarin anticoagulants in most patients, but increased effects and even bleeding have been seen in some patients.
It would be prudent to monitor the effects of concurrent use. In one large review serious problems were identified at about 5 days so it may be prudent to measure the INR just before this point.