Fondazest 2.5mg Injection is an anticoagulant medicine used in the prevention of blood clot formation. This medicine prevents/treat conditions like deep vein thrombosis (blood clots in leg veins), pulmonary embolism (blood clots in the lung), heart attack, and severe angina. This medicine works by inhibiting the action of clotting factors, thereby preventing the conversion of fibrinogen to fibrin, a protein and helps prevent blood clot formation. Common side effects include unusual bleeding, anemia, bruising or swelling.