Reduce the drug Zocor: FDA suggests to doctors

All statins, a popular type of cholesterol-lowering drug, carry a low risk of muscle injury. But patients on the highest dose of the drug simvastatin, most commonly known as Zocor, seem to be at an elevated risk—so doctors should stop prescribing that dose for most people, the Food and Drug Administration has advised.

That dose, 80 milligrams, should continue to be taken only by patients who have taken it for at least 12 months without muscle injury, the agency said Wednesday in a safety announcement.

Everyone else should heed the FDA’s updated labels on simvastatin, and simvastatin-containing drugs such as Vytorin and Simcor. The labels for the first two will reflect the new dose-restriction recommendation, and the labels for all three will offer more guidance about possible interaction risks when used with other drugs.

People take statins, which block an enzyme necessary for the cholesterol-making process, to lower “bad” cholesterol and decrease the risk of heart disease. Statins come in several brands and generics.

Many patients take an 80-milligram version of simvastatin—about 2.1 million people were prescribed a medication containing that dosage last year, the agency said.

The FDA alerted consumers in March 2010 that this dosage may be dangerous after a clinical trial found that patients taking 80-milligram doses of Zocor were more likely to develop myopathy, a type of muscle pain or weakness, than those on the 20-milligram dose (0.9% of participants compared to 0.02%). The labeled risk is 0.53%. A small percentage (0.4%) of the 80-milligram group developed the more severe condition rhabdomyolysis, in which muscle fibers break down and release a kidney-damaging protein into the bloodstream.

So the risk for an individual patient is tiny, but if patients have other drugs from which to choose -- and they do -- the agency essentially says: Why take the chance? In a consumer update, the FDA offered this advice about patients on lower doses of simvastatin:

“And if health care professionals find that patients now taking 40 mg of simvastatin aren’t meeting their LDL cholesterol goal, FDA is advising them to choose a different statin rather than raising the simvastatin dose to 80 mg.”

So as always, talk with your doctor before making any changes to your dose.