View the Inhibitors and Inducers of CYP Enzymes, P-Glycoprotein, and Other Transporters tables

The FDA recently approved three new drugs for treatment of hyperlipidemia. Ezetimibe (ez et' i mibe; Zetia) is the first in a new class of drugs that inhibit intestinal absorption of cholesterol. Extended-release lovastatin (Altocor) is a new formulation of lovastatin (Mevacor, and others). Extended-release niacin plus (immediate-release) lovastatin (Advicor) is the first fixed-dose combination of lipid-lowering drugs.

Changes caused by one drug in the absorption, distribution, metabolism or excretion of another may lead to a pharmacokinetic adverse drug interaction (DN Juurlink et al, JAMA 2003; 289:1652). Additive drug interactions, such as vasodilation caused by both sildenafil (Viagra) and nitrates, can also have adverse effects.

The FDA has approved the oral adenosine triphosphate-citrate lyase (ACL) inhibitor bempedoic acid for use alone (Nexletol – Esperion) and in a fixed-dose combination with the cholesterol absorption inhibitor ezetimibe (Nexlizet) as an adjunct to diet and maximally tolerated statin therapy in adults with heterozygous familial hypercholesterolemia (HeFH) or established atherosclerotic cardiovascular disease (ASCVD) who require additional lowering of LDL-cholesterol (LDL-C). Bempedoic acid is the first ACL inhibitor to be approved in the US.

The FDA recently approved the use of atorvastatin (Lipitor) to reduce the risk of heart attack and stroke in patients without heart disease who have type 2 diabetes plus other risk factors, with or without hypercholesterolemia. The agency also approved the drug's use to reduce the risk of stroke in high-risk nondiabetic patients without heart disease, whether or not they have hypercholesterolemia. Similar indications were previously approved for simvastatin (Zocor).

The National Cholesterol Education Program recommends that LDL-C be lowered to less than 100 mg/dL (2.6 mmol/L) and considers a value <70 mg/dL (1.8 mmol/L) a reasonable goal for patients at very high risk.

The FDA has approved the marketing of pitavastatin (Livalo – Kowa), an HMG-CoA reductase inhibitor (“statin”), for treatment of primary hyperlipidemia or mixed dyslipidemia. It has been available in Japan since 2003. All of the statins now available in the US are listed in the table on page 58.

A reader expressed disappointment that our recent listing of “Some Warfarin Drug Interactions”1 did not include acetaminophen. Perhaps it should have. Acetaminophen can increase the anticoagulant effect of warfarin, particularly with continued use, but it does so inconsistently. The mechanism of this interaction has not been established, but may be related to an acetaminophen metabolite inhibiting vitamin K-epoxide reductase, the target for warfarin’s anticoagulant effect.2Patient susceptibility varies, possibly on a genetic basis; occasional use of acetaminophen generally has little or...

New guidelines from The National Cholesterol Education Program recommend, as a therapeutic option, lowering treatment goals for LDL cholesterol (LDL-C) from <100 mg/dL to <70 mg/dL for patients at very high risk for coronary heart disease and from 130 mg/dL to <100 mg/dL for those at moderately high risk. A likely consequence of these recommendations is increased use of statins and use of higher doses with a concomitant increase in adverse effects.

View the Comparison Table: Some Lipid-Lowering Drugs