BEIJING, June 9 (Xinhuanet) -- The U.S. Food and Drug Administration (FDA) on Wednesday tightened its rules on who should take the highest approved dose of the statin drug simvastatin, cautioning that the drug can cause severe muscle damage.
Simvastatin is the second-most-prescribed drug in the country. It is sold by itself as Zocor and in combination with another cholesterol-lowering drug, ezetimibe, as Vytorin.
Regulators said that patients taking the 80 milligram dose of Zocor, a statin drug, have a higher risk of muscle damage than patients taking lower doses of the drug or similar medications.
The FDA said any patient now taking the 80-milligram dose of simvastatin who has been on it less than a year should be switched to a different cholesterol-lowering statin of equal potency.
Doctors should not prescribe the higher 80 mg dose of simvastatin to patients who are unable to adequately lower their level of [LDL cholesterol] on simvastatin 40 mg, instead they should give those patients another treatment to lower their LDL cholesterol, FDA said in a news release.
Patients taking any dose of simvastatin who are also taking certain anti-fungal drugs, antibiotics or protease inhibitors for treating HIV should also be switched to other statins.
FDA now recommends that no new patients should start taking that dose -- 80 milligrams.
The FDA said the warning is based on clinical trials, studies, reports of side effects by users and prescription data.