deep vein thrombosis
"I am a 39 year old woman with a history of DVT who switched from warfarin to Xarelto . Shortly after starting the medicine I began to experience migraines for the first time. After two weeks of being on it, I began my menstrual period as scheduled. The period was severe bleeding 6 days straight, at that point I went to the ER, I ended up with several blood transfusions that were not helping, my hemoglobin was dropping to dangerous levels. The only thing to be done was an emergency uterine ablation. I believe that blood levels DO actually need to be monitored. My blood was so thin I was not clotting. "