What is a significant risk associated with Gemfibrozil (Lopid)?

Gemfibrozil, a medication primarily used to lower lipid levels in patients with hyperlipidemia, has a notable interaction with warfarin that significantly increases the International Normalized Ratio (INR). This occurs because Gemfibrozil inhibits the enzyme responsible for the metabolism of warfarin, leading to higher concentrations of warfarin in the bloodstream. Consequently, patients may experience an increased risk of bleeding due to elevated INR levels, indicating a greater anticoagulant effect.

This interaction underscores the importance of monitoring INR closely in patients who are on both Gemfibrozil and warfarin, as adjustments to the warfarin dosage may be necessary to maintain therapeutic levels and minimize the risk of bleeding complications.

Understanding the pharmacokinetic interactions between medications, particularly those that affect hepatic enzyme activity, is crucial in pharmacotherapy to ensure patient safety and achieve the desired therapeutic outcomes.