An anticoagulant is a drug (blood thinner) that treats, prevents, and reduces the risk of blood clots-breaking off and traveling to vital organs of the body, which can lead to life threatening situations. Anticoagulants are commonly used medications in the prevention and treatment of thromboembolic disease. Vitamin K antagonists (VKAs), primarily warfarin, have been the most frequently used agents for patients requiring chronic anticoagulation. More recently, newer oral anticoagulants including the direct thrombin inhibitors and factor Xa inhibitors have become available. Bleeding is the major complication of anticoagulant and fibrinolytic therapy. The criteria for defining the severity of bleeding vary considerably between studies, accounting in part for the variation in the rates of bleeding reported. The major determinants of vitamin K antagonist (VKA)-induced bleeding are the intensity of the anticoagulant effect, underlying patient characteristics, and the length of therapy. Iliopsoas hematoma is a rare complication that occurs in patients receiving anticoagulant therapy. The clinical manifestation of iliopsoas hematoma is non-specific. It can mimic orthopedic or neurological disorders, including paraesthesia or paresis of the thigh and leg due to compression of the nerve plexus.

Keywords: Anticoagulant; Vitamin K antagonists (VKAs); Coagulopathy; Newer Oral Anticoagulants; Factor Xa Inhibitors.