Hi As you mentioned that your cholesterol level is 198 mg/dl , however total cholesterol level is normal at upper limit. It would have been better , if you have mentioned the value of LDL ( low density lipoprotein or bad cholesterol in layman terms ). Since your doctor advised atorvatatin 20 mg orally once in day . These are side effects of this drug : headache, nausea, /vomiting , reversible myositis , abdominal pain , insomnia , chest pain alopecia , impotence . But these side effects are minor and if taken for prolong period , so you should not worry because in your case the level of cholesterol is not too high and it will be within normal limit in short period . In my opinion you will get desired result within 10-15 days . So remain in contact with your physician . Good luck. Avoid fried , spicy oily foods and do regular 40 minutes exercise / day ( 5-6 days in a week). Hope this will be useful for you.