Lipitor is a prescription medication designed to lower cholesterol levels and reduce the risk of heart disease. It contains atorvastatin, an active ingredient in the statin class, and is available in tablet form with dosage strengths of 5mg, 10mg, 20mg, 40mg, and 80mg. Lipitor works by decreasing the amount of cholesterol produced by the liver. It is commonly prescribed to decrease low-density lipoprotein (LDL) cholesterol while increasing high-density lipoprotein (HDL) cholesterol. Lipitor is available under several other brand names, including Aztor, Atorva, Atocor, and Atorlip.