What serious interaction is possible when Warfarin is combined with NSAIDs?

When Warfarin is combined with NSAIDs, the most significant interaction that can occur is serious gastrointestinal (GI) bleeding. Both Warfarin, an anticoagulant, and NSAIDs, which are anti-inflammatory medications, can independently increase the risk of bleeding. Warfarin works by inhibiting blood clotting factors in the liver, whereas NSAIDs can cause gastric mucosal injury and reduce platelet function. When these two classes of medications are used together, the risk of GI complications, especially bleeding, is amplified.

Patients taking both medications should be monitored closely for any signs of GI bleeding, such as black or bloody stools, abdominal pain, or vomiting blood. This interaction highlights the importance of careful medication management in patients who may require the combined use of these drugs to prevent adverse outcomes.

Other options do not represent significant interactions with combined use. Increased liver function is not a recognized effect of this combination, nor is increased blood pressure a primary concern. Additionally, the combination does not result in decreased anticoagulant effects; rather, the bleeding risk is the primary concern.