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As an anticoagulant while collecting blood for various investigations. 2.
Coumarin Derivatives Dicoumoral and Warfarin are the derivatives of coumarin.
Mechanism of action It competes with Vit K for reactive sites is the enzymatic processes for formation of prothrombin factors VII, IX, X all of which form in the liver and require Vit K. It blocks the action of Vit K. After effective dose is administered, the coagulant activity decreases to approximately 50 % of normal at end of 12 hrs and to 20% at end of 24 hrs. The process is not blocked immediately must await consumption of pro thrombin and other factors already present in plasma. Normal coagulation returns 1 to 3 days after discontinuing therapy. Uses – they are used as oral anticoagulants in clinical practice. 3.
EDTA
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Ethylene Diamine Tetra Acetic acid or sodium salt of EDTA is a strong anticoagulant.
Mechanism of Action -
by removing calcium from blood
Uses -
Administered intravenously in case of lead poisoning
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Also used as anticoagulant in lab (in vitro).
4. -
Oxalate Compounds It prevents coagulation by forming calciumoxalate, which is precipitated later, thus they reduce blood calcium level. It is used as in vitro anticoagulant.
5. -
Citrates Sodium, Ammonium or Potassium citrate can be used as anticoagulants in lab (invitro). Citrate combines with calcium is blood