Prevents clot formation

  • AT prevents the expansion of a formed thrombus (clot) and the formation of additional clots


Maintains hemostasis

  • AT plays a critical role in maintaining hemostasis
    • Binds irreversibly to thrombin and factor Xa, preventing the conversion of fibrinogen into fibrin1,2
    • Provides 80% of the natural anticoagulant effect against thrombin1,2


Enhances Heparin Effectiveness

  • AT is necessary for the anticoagulation effects of heparin3
  • Heparin is ineffective in the absence or near absence of AT3

THROMBATE III® (antithrombin III [human]) is indicated in patients with hereditary antithrombin deficiency for treatment and prevention of thromboembolism and for prevention of perioperative and peripartum thromboembolism.

Hypersensitivity reactions may occur. Should evidence of an acute hypersensitivity reaction be observed, promptly interrupt the infusion and begin appropriate treatment.

Because THROMBATE III is made from human blood, it may carry a risk of transmitting infectious agents, eg, viruses, the variant Creutzfeldt-Jakob disease (vCJD) agent, and, theoretically, the Creutzfeldt-Jakob disease (CJD) agent. There is also the possibility that unknown infectious agents may be present in the product.

Perform coagulation tests to avoid excessive or insufficient anticoagulation and monitor for bleeding or thrombosis. Measure functional plasma AT levels with amidolytic or clotting assays; do not use immunoassays.

In clinical studies, the most common adverse reactions (≥5% of subjects) were dizziness, chest discomfort, nausea, dysgeusia, and pain (cramps).

The anticoagulant effect of heparin is enhanced by concurrent treatment with THROMBATE III in patients with hereditary AT deficiency. Thus, in order to avoid bleeding, the dosage of heparin (or low molecular weight heparin) may need to be reduced during treatment with THROMBATE III.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit, or call 1-800-FDA-1088.


  1. Maclean PS, Tait RC. Hereditary and acquired antithrombin deficiency: epidemiology, pathogenesis and treatment options. Drugs. 2007;67(10):1429-1440.
  2. Kottke-Marchant K, Duncan A. Antithrombin deficiency. Issues in laboratory diagnosis. Arch Pathol Lab Med. 2002;126:1326-1336.
  3. THROMBATE III® (antithrombin III [human]) Prescribing Information. Grifols.