Why can’t the cholesterol-lowering drug Lipitor be taken with grapefruit or grapefruit juice?
Brad Walters, a student in the School of Pharmacy at Kansas University and an extern at Lawrence Memorial Hospital, said substances in grapefruit juice inhibit the activity of an enzyme involved in the metabolism of Lipitor, or atorvastatin. Enzymes are proteins in the body that break down and inactivate medications. This inhibition increases levels of the drug by between 20 percent and 50 percent, which increases the risk of experiencing serious side effects like severe muscle damage or liver failure. Walters said the following cholesterol-lowering drugs in the same class as Lipitor, statins, also carry this risk if taken with grapefruit juice since the same enzyme is involved in their metabolism: Zocor (simvastatin) and Mevacor (lovastatin). The following statins do not depend on the same enzymes for their metabolism and thus do not interact with grapefruit juice: Pravachol (pravastatin), Lescol (fluvastatin) and Crestor (rosuvastatin).