ezetimibe and simvastatin, Vytorin (cont.)
Omudhome Ogbru, PharmD
Omudhome Ogbru, PharmD
Dr. Ogbru received his Doctorate in Pharmacy from the University of the Pacific School of Pharmacy in 1995. He completed a Pharmacy Practice Residency at the University of Arizona/University Medical Center in 1996. He was a Professor of Pharmacy Practice and a Regional Clerkship Coordinator for the University of the Pacific School of Pharmacy from 1996-99.
Medical and Pharmacy Editor:
Amiodarone (Cordarone), verapamil (Calan Verelan, Isoptin), diltiazem, amlodipine (Norvasc), danazol (Danocrine), ranolazine (Ranexa) cyclosporine (Gengraf, Neoral), 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, amlodipine, or ranolazine should not exceed 10/20 mg, and those taking verapamil or diltiazem should not exceed 10/10 mg of of Vytorin daily.
Patients taking gemfibrozil or danazol should not take Vytorin.
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. Cholestyramine (Questran) decreases the absorption of ezetimibe, and, therefore, Vytorin should be administer two hours before or at least four hours after cholestyramine is administered.
Chinese patients taking more than 1 gram of niacin daily in combination with simvastatin, 40 mg, have an increased risk of muscle-related side effects. Therefore, these patients should not receive Vytorin 10/80 mg combined with niacin doses greater than 1 gram daily. Other doses of Vytorin should be administered cautiously when combined with niacin, 1 gram daily.
PREGNANCY: Vytorin should not be taken during pregnancy because the developing fetus requires cholesterol for development, and Vytorin, due to the simvastatin component, reduces the production of cholesterol. Vytorin should only be administered to women of child bearing age if they are not likely to become pregnant.
NURSING MOTHERS: Because of the risk of adverse effects to the developing infant, Vytorin should not be administered to nursing mothers.
SIDE EFFECTS: The most common side effects of Vytorin are headache, nausea, vomiting, diarrhea, muscle pain, and abnormal liver tests. Hypersensitivity reactions also have been reported. The most serious potential side effects are liver damage and muscle inflammation or breakdown. The simvastatin component of Vytorin is a statin. Therefore it shares side effects, such as liver and muscle damage associated with statins. Serious liver damage caused by statins is rare. More often, statins cause abnormalities of liver tests, and, therefore, periodic measurement of liver tests in the blood is recommended for all statins. Abnormal tests usually return to normal even if a statin is continued, but if the abnormal test value is greater than three times the upper limit of normal, the statin usually is stopped. Liver tests should be measured before Vytorin is started and periodically thereafter or if there is a medical concern about liver damage.
Inflammation of the muscles caused by statins can lead to a serious breakdown of muscle cells called rhabdomyolysis. Rhabdomyolysis causes the release of muscle protein (myoglobin) into the blood. Myoglobin can cause kidney failure and even death. When used alone, statins cause rhabdomyolysis in less than one percent of patients. To prevent the development of rhabdomyolysis, patients taking Vytorin should contact their health care professional immediately if they develop unexplained muscle pain, weakness, or muscle tenderness.
Statins have been associated with increases in HbA1c and fasting serum glucose levels that are seen in diabetes. There are also post-marketing reports of memory loss, forgetfulness, amnesia, confusion, and memory impairment. Symptoms may start 1 day to years after starting treatment and resolve within a median of 3 weeks after stopping the statin.
Reference: FDA Prescribing Information
Last Editorial Review: 5/1/2012
Back to Medications Index
Get the latest health and medical information delivered direct to your inbox FREE!