Buy Xarelto 20mg (rivaroxaban) is an anticoagulant (blood thinner) that prevents the formation of blood clots. Xarelto is used to prevent or treat a type of blood clot called deep vein thrombosis (DVT), which can lead to blood clots in the lungs (pulmonary embolism). A DVT can occur after certain types of surgery. Xarelto is also used in people with atrial fibrillation (a heart rhythm disorder) to lower the risk of stroke caused by a blood clot. Xarelto may also be used for purposes not listed in this medication guide.