Generic Zocor (Simvastatin)

DRUG INTERACTIONS: Decreased elimination of simvastatin could increase the levels of simvastatin in the body and increase the risk of muscle toxicity from simvastatin. Examples of drugs that decrease elimination of simvastatin include erythromycin (E-Mycin), ketoconazole (Nizoral), itraconazole (Sporanox), clarithromycin (Biaxin), telithromycin (Ketek), cyclosporine (Sandimmune), nefazodone (Serzone), and HIV protease inhibitors such as indinavir (Crixivan) and ritonavir (Norvir). Large quantities of grape fruit juice (>1 quart daily) also will increase blood levels of simvastatin.

Amiodarone (Cordarone), verapamil (Calan Verelan, Isoptin), danazol (Danocrine), cyclosporine, niacin (Niacor, Niaspan, Slo-Niacin), gemfibrozil (Lopid) and fenofibrate (Tricor) also may increase the risk of muscle toxicity when combined with simvastatin. Patients taking amiodarone or verapamil should not take more than 20 mg of simvastatin. Patients taking danazol or cyclosporine should not take more than 10 mg of simvastatin.

Simvastatin increases the effect of warfarin (Coumadin) and the blood concentration of digoxin (Lanoxin). Patients taking simvastatin and warfarin or digoxin should be monitored carefully for toxic effects of warfarin and digoxin.

Cholestyramine (Questran, Questran Light) decreases the absorption of simvastatin. Therefore, simvastatin should only be taken 2 hours before or at least 4 hours after cholestyramine administration.