Atorvastatin

Brand Names: Lipitor

Drug Class: HMG-CoA reductase inhibitor (statin)

Overview

Atorvastatin is a statin medication used to lower LDL cholesterol and reduce cardiovascular risk. It works by inhibiting HMG-CoA reductase, decreasing cholesterol production in the liver. It is indicated for primary and secondary prevention of cardiovascular events in appropriate patient populations.

Mechanism of Action

Atorvastatin competitively inhibits HMG-CoA reductase, the rate-limiting enzyme in cholesterol biosynthesis. This inhibition reduces hepatic cholesterol production, leading to upregulation of LDL receptors and increased clearance of LDL cholesterol from the bloodstream.

Indications

  • Reduce risk of myocardial infarction, stroke, revascularization procedures, and angina in adults with multiple CHD risk factors
  • Reduce risk of MI and stroke in adults with type 2 diabetes and multiple CHD risk factors
  • Reduce LDL-C in adults with primary hyperlipidemia
  • Reduce LDL-C in adults and pediatric patients (≥10 years) with heterozygous familial hypercholesterolemia
  • Reduce LDL-C in adults and pediatric patients (≥10 years) with homozygous familial hypercholesterolemia
  • Treat primary dysbetalipoproteinemia
  • Treat hypertriglyceridemia

Common Doses

  • 10 mg
  • 20 mg
  • 40 mg
  • 80 mg

Dosage

Initial dose typically 10-20 mg once daily, may be increased to maximum 80 mg daily based on LDL-C response. Administer at any time of day with or without food.

Contraindications

  • Acute liver failure or decompensated cirrhosis
  • Hypersensitivity to atorvastatin or any tablet excipients

Side Effects

  • Myalgia, arthralgia, diarrhea, nasopharyngitis
  • Increased liver enzymes
  • Muscle pain, tenderness, or weakness (potential myopathy)
  • Rhabdomyolysis (rare but serious)
  • Hyperglycemia
  • Hypersensitivity reactions including anaphylaxis, angioedema, erythema multiforme

Interactions

  • Strong CYP3A4 inhibitors (e.g., clarithromycin, itraconazole, HIV protease inhibitors) increase atorvastatin exposure and risk of myopathy
  • Cyclosporine, gemfibrozil, and other fibrates increase myopathy risk
  • Colchicine may increase risk of myopathy
  • Warfarin: monitor INR as atorvastatin may potentiate anticoagulant effect

Counseling Points

  • Take once daily at any time, with or without food
  • Report unexplained muscle pain, tenderness, or weakness immediately
  • Avoid excessive alcohol consumption
  • Maintain standard cholesterol-lowering diet during treatment
  • Inform healthcare provider of all medications, especially antibiotics and antifungals
  • Routine monitoring of liver enzymes may be recommended