Ezetimibe plus simvastatin, a combination of two anti-cholesterol drugs marketed by Merck/Schering-Plough Pharmaceuticals as Vytorin, is no more damaging to muscles than simvastatin alone, a team at Rush University Medical Center in Chicago reports in the American Journal of Cardiology.

Dr. Michael H. Davidson and colleagues note that ezetimibe reduces cholesterol levels by blocking dietary absorption, while simvastatin works by reducing cholesterol produced by the body.

Previous reports have linked “statin” drugs, like simvastatin, with muscle side effects, but it was unclear if adding ezetimibe would lead to even greater risks.

The investigators compared the muscle safety profiles of 4500 patients in 17 studies who were treated with simvastatin, ezetimibe, or both drugs. The primary comparison was between 1234 patients treated with simvastatin alone and 1236 patients treated with ezetimibe plus simvastatin.

The authors found that the likelihood of muscle problems did not increase (or decrease) when ezetimibe was used in combination with simvastatin. Moreover, none of the patients developed rhabdomyolysis, a potentially fatal condition involving muscle breakdown.

Ezetimibe plus simvastatin does not increase the risk of muscle problems any more than simvastatin alone. However, the combination provides enhanced cholesterol-lowering effects said Davidson.

SOURCE: American Journal of Cardiology, February 2006.