Atorvastatin is a synthetic inhibitor of 3-hydroxy 3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor. It has a longer half life and longer duration of action than that of all other available HMG-CoA inhibitors. We evaluated the efficacy of alternate-day dosing of atorvastatin in comparison with the standard one-daily dose on total cholesterol, low and High-density lipoprotein (LDL and HDL) and triglycerides. This study is a randomized, blinded, and controlled clinical trial. Sixty-six patients with LDL cholesterol of more than 100 mg/dl were enrolled. Baseline fasting lipid profile (total cholesterol, LDL, HDL and triglyceride), liver function tests and creatine kinase were drawn. Patients were randomized to three atorvastatin dose groups. Group I received 10 mg of atorvastatin every day, group II received 20 mg of atorvastatin every day, and group III received 20 mg every other day. After 6 weeks of treatment with atorvastatin, fasting lipid profiles, liver function tests and creatine kinase concentrations were re-taken. Compliance to treatment was assessed at each visit. Of the sixty-six patients enrolled, sixty completed the study. All three regimens significantly reduced total cholesterol and LDL compared to baseline. No statistically significant difference existed between the three groups in regards to total or a percentage decrease in total cholesterol and LDL cholesterol at 6 weeks compared to baseline. All regimens were well tolerated and none of the patients showed significant elevation of liver enzyme or creatine kinase during the course of the study. In conclusions the alternate-day dosing of atorvastatin is an efficacious and safe alternate to daily dosing and yet inexpensive.