What is a common side effect associated with warfarin?

Warfarin is an anticoagulant that works by inhibiting vitamin K-dependent clotting factors, thereby reducing the ability of the blood to clot. A common side effect associated with this medication is bleeding complications, which can occur because warfarin effectively lowers the blood's capacity to form clots. Patients taking warfarin are at an increased risk for various forms of bleeding, such as gastrointestinal bleeding, intracranial bleeding, or excessive bleeding from cuts and injuries.

Monitoring of the International Normalized Ratio (INR) is crucial for patients on warfarin to ensure that their blood's clotting ability remains within a safe range to minimize the risk of these potentially serious bleeding events. If a patient's INR becomes too high, indicating excessive anticoagulation, they may require dose adjustments or other interventions to reduce their bleeding risk.

While nausea, headaches, and skin rashes can occur with various medications, they are not recognized as common or serious side effects specifically associated with warfarin, making bleeding complications the most significant concern for patients using this drug.