Based on anti-Xa levels, danaparoid has a half-life of approximately 25 h. Although danaparoid was shown to be effective for the prevention of venous thrombosis in high-risk patients, it is no longer marketed for this indication. Currently, its use is limited to the management of patients with HIT; it is discussed in greater detail in the article on HIT in this supplement.32 Danaparoid is the only agent that has been evaluated for HIT in a randomized clinical trial, wherein it was reported to be signi cantly better than dextran. High success rates in the treatment of HIT have also been observed in retrospective studies. Danaparoid is approved for the treatment of HIT in some countries (eg, The Netherlands, Belgium, New Zealand) but not in the United States. Danaparoid does not prolong the INR. This facili- tates monitoring when transitioning patients with to plasma proteins other than AT, and most of the compound is bound to AT.201 Based on its almost complete bioavailability after subcutaneous injection, lack of variability in anticoag- ulant response, and long half-life, fondaparinux can be administered subcutaneously once daily in xed doses without coagulation monitoring. Fondaparinux is nearly completely dependent on renal clearance; thus, it is contraindicated in patients with renal insuf- ciency (CrCl,30 mL/min). 1.3.3 Dosing and Monitoring: Fondaparinux is given at a xed dose of 2.5 mg daily for thrombopro- phylaxis and for the treatment of acute coronary syndromes. For treatment of DVT or pulmonary embolism, the drug is given at a dose of 7.5 mg for patients with a body weight of 50 to 100 kg; the dose is decreased to 5 mg for patients weighing,50 kg and increased to 10 mg in those weighing.100 kg. Fondaparinux has not been monitored in clinical studies. Therefore, routine coagulation monitoring is not recommended. 