Atorvastatin

Atorvastatin is a lipid-lowering medication in the statin class. It acts as a selective, competitive inhibitor of the enzyme HMG-CoA reductase, which plays a central role in hepatic cholesterol synthesis. By lowering hepatic cholesterol production, atorvastatin upregulates LDL receptors on hepatocytes, increasing clearance of low-density lipoprotein (LDL) from the bloodstream. The result is a reduction in LDL cholesterol, with additional modest decreases in triglycerides and a small rise in high-density lipoprotein (HDL) cholesterol.

Indications for atorvastatin include reduction of cardiovascular risk in adults with elevated cholesterol and in those with established atherosclerotic cardiovascular disease, as well as use in familial hypercholesterolemia and certain cases of mixed dyslipidemia. It is commonly used as part of a comprehensive risk-reduction strategy that includes diet and lifestyle changes.

Dosing typically starts at 10 or 20 mg once daily, with adjustments up to 80 mg daily based on LDL-C targets and tolerability. It can be taken at any time of day. Because atorvastatin is primarily metabolized by CYP3A4, concomitant use with strong CYP3A4 inhibitors or certain other drugs can raise the risk of adverse effects, particularly myopathy and rhabdomyolysis. Grapefruit juice should be avoided in some regimens.

Common adverse effects include myalgia, elevated liver enzymes, and, less frequently, constipation or nausea. Rare but serious risks include myopathy and rhabdomyolysis, especially with drug interactions or high doses. Contraindications include active liver disease and pregnancy or breastfeeding. Baseline and periodic monitoring of liver enzymes and, when indicated, creatine kinase is recommended. Atorvastatin was approved in the United States in the mid-1990s and remains one of the most prescribed statins.