When I was first on warfarin I reached my therapeutic range and stayed there fairly easily. Then I changed to Dabigatran and then I was put back on warfarin for an ablation. I have had to stay on warfarin because I have a blood clot. I should have been in therapeutic range 3.0 - 3.5 since beginning of September but I have only achieved that for a few days. Yesterday I had another check and I had gone down in a week from 2.6 to 2.1 even with an increase in dosage. What is going on?! I am really concerned that I will have a stroke.