Mactor is in a group of drugs called HMG CoA reductase inhibitors, or "statins." Mactor 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). Mactor 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. Mactor is used in adults and children who are at least 10 years old. Mactor may also be used for purposes not listed in this medication guide.

Mactor 20 Tablet 10's may cause a breakdown of skeletal muscle tissue, leading to kidney failure. This condition usually occurs in the elderly, people with kidney disease, and poorly controlled hypothyroidism (underActive thyroid). Mactor 20 Tablet 10's should not be prescribed to children less than 10 years of age. You should contact a doctor before if you have had an allergic reaction to Mactor 20 Tablet 10's, have liver problem (jaundice, liver cirrohosis), or kidney problems, pregnant or planning to get pregnant, breastfeeding, have severe lung disease, have a previous heart attack or stroke caused by bleeding in the brain, have hypothyroidism, drink more than 2 servings of alcohol per day and have a muscle disorder (fibromyalgia) and damaged muscle tissue (rhabdomyolysis).