Antikoagulantseid

Antikoagulantseid is a term used to refer to substances that reduce or prevent blood coagulation. In medical contexts it denotes anticoagulant drugs, which are used to prevent or treat thrombosis by interfering with the coagulation cascade. They are commonly prescribed to lower stroke risk in atrial fibrillation, prevent venous thromboembolism after surgery, and treat existing clots.

Most anticoagulants work by inhibiting specific coagulation factors. Vitamin K antagonists, such as warfarin, reduce production of factors II, VII, IX, and X. Direct oral anticoagulants (DOACs) include direct thrombin inhibitors (dabigatran) and direct factor Xa inhibitors (rivaroxaban, apixaban, edoxaban). Parenteral anticoagulants like unfractionated heparin and low-molecular-weight heparins enhance antithrombin activity. DOACs are generally given in fixed doses and require less routine monitoring than warfarin, while heparins are often used short term or for bridging.

Indications include prevention of stroke in nonvalvular atrial fibrillation, treatment or prevention of venous thromboembolism, and prophylaxis after certain surgeries. DOACs are not typically used for mechanical heart valves, where warfarin remains the standard due to evidence and guidelines. Monitoring and dosing considerations vary: warfarin requires regular INR checks and dietary vitamin K management; DOACs require assessment of kidney function and awareness of drug interactions. Common interactions involve antiplatelet drugs, NSAIDs, and certain antibiotics.

Safety and reversal: the main risk is bleeding. Reversal strategies exist, such as vitamin K for warfarin; specific agents like idarucizumab for dabigatran and andexanet alfa for factor Xa inhibitors, plus nonspecific reversal with prothrombin complex concentrates in some cases. History of anticoagulants dates to the mid-20th century, with warfarin becoming widespread in the 1950s and DOACs emerging in the 2000s.