Lipitor (atorvastatin) belongs to a group of drugs called HMG CoA reductase inhibitors, or statins.Lipitor reduces levels of bad cholesterol  and triglycerides in the blood, while increasing levels of good cholesterol .Lipitor is used to treat high cholesterol, and to lower the risk of stroke, heart attack, or other heart complications in people with type 2 diabetes, coronary heart disease, or other risk factors.