Based on review of data from a large clinical trial and data from other sources, the U.S. Food and Drug Administration (FDA) released a warning on March 19, 2010 about an increased risk of muscle injury in patients taking the highest approved dose of the cholesterol-lowering medication, Zocor* (simvastatin) 80 mg, compared to patients taking lower doses of simvastatin and possibly other drugs in the “statin” class.

The FDA also warned that mixing Zocor with certain other drugs also increases patients’ risk of muscle injury, including the rare but serious complication known as rhabdomyolysis. Rhabdomyolysis can sometimes result in fatal kidney damage.

“Other drugs” includes incidental exposure to niacin-containing products as innocent as breakfast cereal.

The combination products Vytorin and Simcor also contain simvastatin, the active ingredient in Zocor. Zocor is a member of the class of drugs known as statins. All statin drugs carry a risk of muscle damage, but new data suggest that this risk may be particularly high for the 80 milligram dose of Zocor.

The data come from the SEARCH study, in which muscle damage was seen in nearly 1% of patients taking the 80 milligram dose of Zocor but in only 0.02% of patients taking the 20 milligram dose of Zocor.

Rhabdomyolysis was rare in the SEARCH study. It happened in only 11 of 6,031 patients (0.02%) in group taking the 80 milligram dose of Zocor, but was not seen in patients taking the 20 milligram dose.

Source : FDA

As always, consult your physician before altering your prescribed medication routine.