Ticagrelor is used to prevent a serious or life-threatening heart attack or stroke, or death in people who have had a heart attack or who have acute coronary syndrome (ACS; blockage of blood flow to the heart). It is also used to prevent blood clots from forming in people who have received coronary stents (metal tubes surgically placed in clogged blood vessels to improve blood flow) to treat ACS. Ticagrelor is used to decrease the risk of a first-time heart attack or stroke in people at risk with coronary artery disease (CAD; reduced blood flow to the heart). It is also used to decrease the risk of another more serious stroke in people who are having a mild to moderate stroke or a transient ischemic attack (TIA; ministroke). Ticagrelor is in a class of medications called antiplatelet medications. It works by preventing platelets (a type of blood cell) from collecting and forming clots that may cause a heart attack or stroke.