2.3. Fondaparin

Fondaparin (Arixtra®) is a synthetic pentasaccharide that closely resembles the pentasaccharide naturally occurring in the UFH and LMWH. It is an antithrombin-mediated factor Xa inhibitor that is devoid of any anti-factor IIa (thrombin) activity [15]. It is used for treating patients with acute coronary syndrome and heparin-induced thrombocytopenia. It is indicated also for certain patients with thrombophlebitis in a fixed dose of 2.5 mg daily s.c. Laboratory monitoring is not needed; however, if necessary fondaparin levels should only be determined using assays that use known fondaparin concentrations to generate their calibration curve. The use of fondaparin in patients with creatinine clearance below 30 mL/min is contraindicated [2]. side effect of vitamin K antagonist therapy is skin necrosis that develops at therapy initiation

An Overview of the Anticoagulant Drugs Used in Routine Clinical Practice

http://dx.doi.org/10.5772/intechopen.76206

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Dabigatran etexilate (Pradaxa®) is a low-molecular weight prodrug that exhibits no pharmacological activity. After oral administration, dabigatran etexilate is converted to its active form, dabigatran, a potent, competitive and reversible direct thrombin inhibitor [18]. The binding of dabigatran to thrombin is specific and selective and includes both free and thrombus-bound thrombin. Maximal blood concentration of dabigatran is reached after 1–3 h after the intake [18]. About 35% of the drug is bound to plasma proteins. Eighty percent of dabigatran is excreted through the kidneys [18]. Dabigatran half-life is 14–17 h [18]. It is given in fixed doses of either 150 or 110 mg twice daily in patients with atrial fibrillation and 150 mg twice daily in patients with VTE [19, 20]. Prophylactic doses after total hip or knee replacement are 220 or

The anticoagulant effect of dabigatran is predictive and, therefore, requires no regular laboratory monitoring. During dabigatran therapy, APTT and thrombin time (TT) are prolonged, but these two tests can only offer a rough approximation of dabigatran blood concentration. In certain situations when dabigatran concentration needs to be assessed, a specific test must be

Rivaroxaban (Xarelto®) directly inhibits factor Xa. It selectively binds both free and prothrombin complex bound factor Xa and in this way inhibits thrombin and clot formation. Peak blood concentration is achieved after 1–3 h after drug ingestion. As much as 95% of the drug is bound to plasma protein. One-third of the drug is excreted through kidneys, the other two-thirds are metabolized in the liver. The drug half-life is 8–13 h [1, 24]. Therapeutic doses are 20 and 15 mg once daily for patients with atrial fibrillation [25]. Patients with VTE are treated with 15 mg twice daily for the first 3 weeks, followed by 20 mg once daily [26, 27]. The drug must always be ingested with food. The prophylactic dose for patients with total hip or knee replacement is

No laboratory monitoring of therapy is needed due to the predictive effect of the drug. Rivaroxaban prolongs PT; however, when an assessment of the drug blood level is needed, an

Apixaban (Eliquis®) directly and reversibly inhibits factor Xa. Maximal blood concentration of the drug is achieved 3–4 h after ingestion. As much as 87% of the drug is bound to blood protein. Twenty-seven percent of the drug is excreted through kidneys and the remainder through the liver. The drug half-life is 12 h [31]. Patients with atrial fibrillation are treated with

and is a consequence of acute thrombosis of subcutaneous venules and capillaries [1].

150 mg once daily with only half the dose given as the first dose after surgery [21].

used, such as modified thrombin time or a chromogenic assay [22, 23].

anti-Xa test calibrated to rivaroxaban should be used [30].

3.2. Direct oral anticoagulants

3.2.1. Dabigatran

3.2.2. Rivaroxaban

10 mg once daily [28, 29].

3.2.3. Apixaban
