Definition
Atorvastatin (INN) is a member of the drug class known as statins, used for lowering cholesterol and thereby reducing cardiovascular disease. Atorvastatin inhibits a rate-determining enzyme located in hepatic tissue used in cholesterol synthesis, which lowers the amount of cholesterol produced. This also has the effect of lowering the total amount of LDL cholesterol; Atorvastatin is a member of the drug class known as statins, used for lowering cholesterol and thereby reducing cardiovascular disease. Atorvastatin inhibits a rate-determining enzyme located in hepatic tissue used in cholesterol synthesis, which lowers the amount of cholesterol produced. This also has the effect of lowering the total amount of LDL cholesterol; As with other statins, atorvastatin is a competitive inhibitor of HMG-CoA reductase. Unlike most others, however, it is a completely synthetic compound. HMG-CoA reductase catalyzes the reduction of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) to mevalonate, which is the rate-limiting step in hepatic cholesterol biosynthesis. Inhibition of the enzyme decreases de novo cholesterol synthesis, increasing expression of low-density lipoprotein receptors (LDL receptors) on hepatocytes. This increases the LDL uptake by the hepatocytes, decreasing the amount of LDL in the blood. [HMDB]
Description
Atorvastatin (Lipitor) is a member of the drug class known as statins. It is used for lowering cholesterol. Atorvastatin is a competitive inhibitor of hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase, the rate-determining enzyme in cholesterol biosynthesis via the mevalonate pathway. HMG-CoA reductase catalyzes the conversion of HMG-CoA to mevalonate. Atorvastatin acts primarily in the liver. Decreased hepatic cholesterol levels increases hepatic uptake of cholesterol and reduces plasma cholesterol levels.
General Information
- Metabolism: Atorvastatin is extensively metabolized to ortho- and parahydroxylated derivatives and various beta-oxidation products. In vitro inhibition of HMG-CoA reductase by ortho- and parahydroxylated metabolites is equivalent to that of atorvastatin. Approximately 70% of circulating inhibitory activity for HMG-CoA reductase is attributed to active metabolites. CYP3A4 is also involved in the metabolism of atorvastatin.
- Uses/Sources: May be used as primary prevention in individuals with multiple risk factors for coronary heart disease (CHD) and as secondary prevention in individuals with CHD to reduce the risk of myocardial infarction (MI), stroke, angina, and revascularization procedures. May be used to reduce the risk of cardiovascular events in patients with acute coronary syndrome (ACS). May be used in the treatment of primary hypercholesterolemia and mixed dyslipidemia, homozygous familial hypercholesterolemia, primary dysbetalipoproteinemia, and/or hypertriglyeridemia as an adjunct to dietary therapy to decrease serum total and low-density lipoprotein cholesterol (LDL-C), apolipoprotein B (apoB), and triglyceride concentrations, while increasing high-density lipoprotein cholesterol (HDL-C) levels.
- Route of Exposure: Atorvastatin is rapidly absorbed after oral administration with maximum plasma concentrations achieved in 1 to 2 hours. The absolute bioavailability of atorvastatin (parent drug) is approximately 14% and the systemic availability of HMG-CoA reductase inhibitory activity is approximately 30%. The low systemic bioavailability is due to presystemic clearance by gastrointestinal mucosa and first-pass metabolism in the liver.
Toxicity
- Carcinogenicity: No indication of carcinogenicity to humans (not listed by IARC).
- Toxicity: Generally well-tolerated. Side effects may include myalgia, constipation, asthenia, abdominal pain, and nausea. Other possible side effects include myotoxicity (myopathy, myositis, rhabdomyolysis) and hepatotoxicity. To avoid toxicity in Asian patients, lower doses should be considered.
Mechanism of Action
| Target Name | Mechanism of Action | References |
|---|---|---|
|
Aryl hydrocarbon receptor 3-hydroxy-3-methylglutaryl-coenzyme A reductase Dipeptidyl peptidase 4 |
12808485 18068977 23703578 15474503 11752352 17327465 15109613 15748157 12769127 |