Atorvastatin, sold under the brand name Lipitor among others, is a statin medication used to prevent cardiovascular disease in those at high risk and to treat abnormal lipid levels.

[6] Like all statins, atorvastatin works by inhibiting HMG-CoA reductase, an enzyme found in the liver that plays a role in producing cholesterol.

[29] There is evidence from systematic review and meta-analyses that statins, particularly atorvastatin, reduce both decline in kidney function (eGFR) and the severity of protein excretion in urine,[30][31][32] with higher doses having greater effect.

[33] Prior to contrast medium (CM) administration, pre-treatment with atorvastatin therapy can reduce the risk of contrast-induced acute kidney injury (CI-AKI) in people with pre-existing chronic kidney disease (CKD) (eGFR < 60mL/min/1.73m2) who undergo interventional procedures such as cardiac catheterisation, coronary angiography (CAG) or percutaneous coronary intervention (PCI).

[34] Atorvastatin therapy can also help to prevent in-hospital dialysis post CM administration, however there is no evidence that it reduces all-cause mortality associated with CI-AKI.

[34][35] Overall, the evidence concludes that statin therapy, irrespective of the dose, is still more effective than no treatment or placebo at reducing the risk of CI-AKI.

A recent meta-analysis suggested that statins with longer half-lives, including atorvastatin, may also be more effective at lowering LDL cholesterol if taken in the evening.

[40] However, the only study included in the meta-analysis of atorvastatin in people with heart disease did not specifically investigate if morning or evening dosing was more effective for reducing LDL cholesterol.

The following have been shown to occur in 1–10% of people taking atorvastatin in clinical trials: muscle pain, tenderness, or weakness lack of energy or extreme tiredness and weakness fever chest pain unusual bleeding or bruising loss of appetite pain in the upper right part of the stomach flu-like symptoms dark colored urine yellowing of the skin or eyes rash hives itching difficulty breathing or swallowing swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs hoarseness[71] Atorvastatin has been associated with a small increase in fasting blood glucose levels over a 2-year period, particularly in patients with Type 2 Diabetes, however evidence is conflicting and clinical significance of this increase has not been determined.

[75][76][77][78] A 2012 meta-analysis found that statin therapy might reduce the risk of pancreatitis in people with normal or mildly elevated blood triglyceride levels.

While studies have suggested that the combined use of statins and the fibrate drug class (such as gemfibrozil, fenofibrate) may increase the risk of myopathy and rhabdomyolysis, there is insufficient evidence to firmly establish this association with atorvastatin.

Only rarely, though, barbiturates, carbamazepine, efavirenz, nevirapine, oxcarbazepine, rifampin, and rifamycin,[90] which are also CYP3A4 inducers, can decrease the plasma concentrations of atorvastatin.

[56] The increase in digoxin levels due to atorvastatin is a 1.2 fold elevation in the area under the curve (AUC), resulting in a minor drug-drug interaction.

This finding initially gave rise to concerns of toxicity, and in 2000, it was recommended that people taking atorvastatin should not consume grapefruit juice "in an unsupervised manner.

The mean volume of distribution of atorvastatin is approximately 381 L. It is highly protein bound (≥98%), and studies have shown it is likely secreted in human breastmilk.

This interaction was tested in vitro with concurrent administration of erythromycin, a known CYP3A4 isozyme inhibitor, which resulted in increased plasma concentrations of atorvastatin.

Geriatric people (>65 years old) exhibit altered pharmacokinetics of atorvastatin compared to young adults, with mean AUC and Cmax values that are 40% and 30% higher, respectively.

[105][106] Another genetic variant that showed genome wide significance in Caucasians was the SNP rs10455872 in the LPA gene that lead to higher Lp(a) levels which cause an apparent lower LDL-c response to atorvastatin.

[105] These studies were in Caucasian population, more research with a large cohort need to be conducted in different ethnicities to identify more polymorphisms that can affect atorvastatin pharmacokinetics and treatment response.

An early enantioselective route to atorvastatin made use of an ester chiral auxiliary to set the stereochemistry of the first of the two alcohol functional groups via a diastereoselective aldol reaction.

[110][better source needed] Bruce Roth, who was hired by Warner-Lambert as a chemist in 1982, had synthesized an "experimental compound" codenamed CI 981 – later called atorvastatin.

[107][111][113][114][115] Warner-Lambert management was concerned that atorvastatin was a me-too version of rival Merck & Co.'s orphan drug lovastatin (brand name Mevacor).

[112] Nevertheless, Bruce Roth and his bosses, Roger Newton and Ronald Cresswell, in 1985, convinced company executives to move the compound into expensive clinical trials.

[111] From 1996 to 2012, under the trade name Lipitor, atorvastatin became the world's best-selling medication of all time, with more than $125 billion in sales over approximately 14.5 years.

[130] In other countries, atorvastatin calcium is made in tablet form by generic medication makers under various brand names including Atoris, Atorlip, Atorva, Atorvastatin Teva, Atorvastatina Parke-Davis, Avas, Cardyl, Liprimar, Litorva, Mactor, Orbeos, Prevencor, Sortis, Stator, Tahor, Torid, Torvacard, Torvast, Totalip, Tulip, Xarator, and Zarator.

[133][134] On 9 November 2012, Indian drugmaker Ranbaxy Laboratories Ltd. voluntarily recalled 10-, 20- and 40-mg doses of its generic version of atorvastatin in the United States.