Even though most people do not experience any problems while taking simvastatin (Zocor®), side effects are possible. In clinical studies, some of the most commonly reported side effects included headache, constipation, stomach pain, and upper respiratory tract infections. There are also a number of rare side effects of simvastatin that were reported in less than 1 percent of people taking the drug, including insomnia, spinning sensation, and muscle aches.
(Click Simvastatin Side Effects for a more complete list of potential side effects, including other common and rare problems. You can also click any of the links in the box to the right for specific information.)