Statins are the first line of defense against high cholesterol and, luckily, fewer than 5% of patients have side effects, says Ruwanthi Titano, M.D., assistant clinical professor of cardiology at Mount Sinai Beth Israel in New York City. The most common one? Achy, tired muscles, known as statin-associated muscle symptoms (SAMS). If the soreness is intolerable, your doctor might switch you to a statin with fewer SAMS-related side effects such as pravastatin or pitavastatin, says Dr. Titano. (Though, studies have shown that when people learn about the possibility of SAMS, they are much more likely to complain about muscle pain, even if they are taking a placebo.)