Information about statin side effects is available at MayoClinic.org and FDA.gov. Muscle pain is the side effect statin users experience most frequently, notes Mayo Clinic. The pain can be mild or rise to a level that impedes a patient's walking and other daily activities.
Some statin users report impaired mental function, including confusion and memory loss, according to the U.S. Food and Drug Administration. Other users may experience blood sugar level elevations and an increased risk of developing type 2 diabetes. The statin lovastatin, marketed as Mevacor, interacts with certain medications, leading to a heightened risk of muscle damage. Serious liver injury related to statin use occurs in rare instances.