Thank you for asking on HealthcareMagic.com. Lipitor (atorvastatin) reduces levels of bad cholesterol (low-density lipoprotein, or LDL) and triglycerides in the blood, while increasing levels of good cholesterol (high-density lipoprotein, or HDL). Stop taking Lipitor and call your doctor at once if you have any of these serious side effects: - unexplained muscle pain, tenderness, or weakness; - fever, unusual tiredness, and dark colored urine; - increased thirst, increased urination, hunger, dry mouth, fruity breath odor, drowsiness, dry skin, blurred vision, weight loss; - or nausea, upper stomach pain, itching, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes) Even most common side effects are less than 10% of cases: - headache - lower back or side pain - painful or difficult urination - stuffy or runny nose You doctor may order some control tests such as liver or kidney function test, cratinemia, BUN each 3-6 months. Please don t forget to give your valuable feedback and five star rating, to help me assist you in a better way. Click at I Find This Answer Helpful too . Please, write a review about your experience with me.