Anticoaguleeritute

Anticoaguleeritute, commonly referred to as anticoagulants, are drugs that reduce the blood’s tendency to clot. They help prevent the formation or growth of clots in blood vessels and are used to treat active thrombosis and to reduce the risk of future events in at‑risk patients. They do not dissolve existing clots but limit their expansion and promote safer blood flow.

Anticoagulants are usually classified by their mechanism. Vitamin K antagonists (for example warfarin and acenocoumarol) inhibit synthesis of vitamin K–dependent clotting factors, leading to a gradual anticoagulant effect. Direct oral anticoagulants (DOACs) include inhibitors of thrombin (dabigatran) and factor Xa inhibitors (rivaroxaban, apixaban, edoxaban); they have more predictable effects and often require less routine monitoring. Heparins, including unfractionated heparin and low molecular weight heparins (such as enoxaparin), enhance the activity of antithrombin to block multiple coagulation factors, and fondaparinux is a synthetic factor Xa inhibitor. These agents can be given parenterally or orally, depending on the drug.

Clinical uses include stroke prevention in atrial fibrillation, treatment and secondary prevention of venous thromboembolism, and prophylaxis of thrombosis after surgery or in high‑risk medical conditions. Warfarin is still used in certain settings such as mechanical heart valves or valvular disease; DOACs are commonly chosen for nonvalvular atrial fibrillation and nonvalvular venous thromboembolism.

Safety and monitoring vary by drug. Warfarin requires regular INR monitoring; unfractionated heparin requires aPTT monitoring; DOACs generally need less monitoring but dose adjustments may be needed for renal impairment. Bleeding is the main risk, and specific reversal strategies exist for different agents (for example vitamin K for warfarin, idarucizumab for dabigatran, and andexanet alfa for certain factor Xa inhibitors). Drug interactions and patient-specific factors are important considerations in dosing and choice of agent.