I managed to get corneal ulcers in both eyes a couple of weeks ago. The eye doctor thought it was due to wearing contact lenses and having very dry eyes. I was prescribed antibiotic eye drops for 7 days - exocin (ofloxacin). Took my INR yesterday and in a week it had gone from an in range 3.8 (my range is 3.5-4.0) and had rocketed to 8.0!! I can't think of anything I have changed aside from the eye problem and using the eye drops. I did ask the eye doctor whether it would affect my INR and he said no as they were drops. I just wondered whether anyone else has found that eye drops can alter INR.