The FDA has issued a warning that the risk of severe muscle and kidney damage from the cholesterol drug simvastatin is higher than previously thought.
Marketed under brand names including Zocor, Vytorin and Simcor, simvastatin is part of a drug family known as statins, all of which are known to expose patients to a risk of muscle damage. In some cases, this damage can take the form of a condition known as rhabdomyolysis and can lead to kidney failure and even death.
New research suggests that the risk of muscle injury, including rhabdomyolysis, is significantly higher in patients who take the highest approved dose (80 milligrams) of the drug. The risk of muscle damage is an astonishing 50 times higher in patients taking the 80 milligram dose than in patients taking the 20 milligram dose.
Eleven cases of rhabdomyolysis were reported among 6,031 patients taking 80 milligrams of simvastatin per day, and none in those taking 20 milligrams.
Another study found that patients of Chinese descent were at a heightened risk of muscle damage if they took both 80 milligrams of simvastatin on top of any medication containing niacin.
Patients of all ethnic backgrounds taking more than 40 milligrams of simvastatin were at heightened risk of muscle damage if they were also taking the angina/blood pressure medicine diltiazem (marketed as Cardizem, Cartia, Dilacor, Diltia and Tiazac). Patients taking more than 20 milligrams per day were at a higher risk of muscle damage if they also took the arrhythmia drug amiodarone (marketed as Cordarone and Pacerone) or the drug verapamil (marketed as Calan, Covera, Isoptin and Verelan), which is used to treat angina, arrhythmia, high blood pressure, cluster headaches and migraine.
The FDA issued a categorical warning that patients taking any of the following drugs should not take more than a 10 milligram dose of simvastatin: Cyclosporine, Danazol and Gemfibrozil.
Patients who should never take simvastatin include those taking HIV protease inhibitors, Clarithromycin, Erythromycin, Itraconazole, Ketoconazole, Nefazodone or Telithromycin.