Description
Why It’s Done:
This test is ordered to:
• Diagnose antithrombin III deficiency, a hereditary or acquired disorder that increases the risk of blood clots
• Evaluate unexplained or recurrent venous thromboembolism (deep vein thrombosis or pulmonary embolism)
• Monitor patients on heparin therapy, as antithrombin is required for heparin’s anticoagulant effect
• Investigate causes of recurrent miscarriage or clotting disorders
Preparation:
• No special preparation is usually required.
• Inform your healthcare provider about any blood thinners or anticoagulant medications you are taking, as these may affect test results.
• Blood is drawn from a vein, usually in the arm.
• Fasting is not necessary
