low molecular weight heparin + vitamin K antagonist

Combination of two anticoagulant drug classes: low molecular weight heparins (LMWHs) and vitamin K antagonists (VKAs). LMWHs act by potentiating antithrombin III and inhibiting Factor Xa, leading to reduced thrombin formation and impaired clot development. VKAs (most commonly warfarin) inhibit the cyclic interconversion of vitamin K in the liver, thereby indirectly reducing the synthesis of vitamin K-dependent clotting factors II, VII, IX, and X. This dual therapy is used primarily for the treatment and prevention of venous thromboembolism (VTE), particularly during the initiation of anticoagulation: LMWH is typically used first, then overlapped with a VKA until the VKA's effect is established. Both drugs act via distinct mechanisms to reduce thrombosis risk.