Plasma concentrations of these agents may be elevated, increasing the pharmacologic effects and risk of adverse reactions. Monitor the clinical response and for adverse reactions. Adjust the dose of these agents as needed.
Gemfibrozil pharmacologic effect may be decreased. Separate administration times by at least 2 h.
Cyclosporine pharmacologic effect may be decreased. Monitor whole blood cyclosporine concentrations. Adjust the dose of cyclosporine as indicated and observe the patient for signs of toxicity or rejection when gemfibrozil therapy is stopped or started, respectively.
HMG-CoA reductase inhibitors (eg, lovastatin)
Increases risk of rhabdomyolysis. If combined use cannot be avoided, frequently monitor for symptoms and signs of rhabdomyolysis and myopathy. If myositis is suspected or diagnosed, discontinue gemfibrozil treatment.
Oral anticoagulants (eg, warfarin)
Anticoagulant effect may be increased. Monitor coagulation parameters. Adjust the anticoagulant dose as needed.
Repaglinide plasma concentrations may be greatly increased and prolonged, increasing the risk of severe and protracted hypoglycemia. Coadministration is contraindicated.
Sulfonylureas (eg, glyburide)
Increased hypoglycemic effects may occur. Monitor blood glucose concentrations when gemfibrozil is started or stopped. Adjust the sulfonylurea dose accordingly.
Thiazolidinediones (eg, pioglitazone)
The risk of hypoglycemia and other adverse reactions (eg, peripheral edema) may be increased. Monitor blood glucose concentrations and for adverse reactions when gemfibrozil is stopped or started. Adjust the thiazolidinedione dose accordingly.