These drugs work by improving a person's cholesterol level and are frequently used in people with heart failure. The most common cause of heart failure is coronary artery disease, caused by a narrowing of the coronary arteries due to a build up of cholesterol (a plaque). These drugs are very effective in preventing the development of plaques which may eventually lead to a shortage of oxygen in your heart (ischaemia) or a heart attack.
Muscle pain (myalgia) is a relatively common but important side effect of statins. You should notify your doctor if you develop unexplained muscle pain, tenderness or weakness. Your doctor will then be able to do a blood test that will indicate if your symptoms are due to statin therapy.
Your doctor will probably want to monitor your cholesterol levels while you are taking a statin in order to decide which dose is the most appropriate. In addition, your doctor can alter your dose or switch the statin you are receiving if you experience muscle pain related to your statin therapy.