Like all medicines, Xarelto can cause side effects, although not everybody gets them. Like other similar medicines (antithrombotic agents), Xarelto may cause bleeding which may potentially be life threatening. Excessive bleeding may lead to a sudden drop in blood pressure (shock).hen to take Xarelto. Take the tablet(s) every day until your doctor tells you to stop. Try to take the tablet(s) at the same time every day to help you to remember it. Your doctor will decide how long you must continue treatment.