FDA strengthens safety warnings for Lipitor, Crestor, Zocor

The US Food and Drug Administration (FDA) has updated the labels of several statins to reflect an increased risk of diabetes and memory loss.

The affected cholesterol-lowering medications include Pfizer's Lipitor (atorvastatin), AstraZeneca's Crestor (rosuvastatin) and Merck & Co's Zocor (simvastatin).

Labels have been revised to reflect data from studies that patients being treated with statins "may have a small increased risk of increased blood sugar levels and of being diagnosed with type 2 diabetes mellitus".

Cognitive effects have also been reported with statin use, with labels updated to include information about some patients experiencing memory loss and confusion, although the FDA said these reports generally have "not been serious" and that discontinuing statin use reversed any symptoms.

As well as these extra warnings, the labels have also been revised to remove the need for routine monitoring of liver enzymes in patients using the drugs.

Early clinical trials had indicated possible liver damage related to statin use, and the FDA initially advised healthcare professionals to regularly test their patients' liver enzyme levels.

However, the agency has now said that serious liver injury with statins is "rare and unpredictable" in individual patients, with routine monitoring ineffective in preventing the side effect.

Liver enzyme tests are now recommended before starting statin therapy, with follow-up tests only necessary if there are symptoms of liver damage.

Others statins to be affected by label updates are Lescol (fluvastatin), Mevacor (lovastatin), Altoprev (lovastatin extended-release), Livalo (pitavastatin) and Pravachol (pravastatin).

Certain combination products involving the affected medicines have also had their labels updated and there was an additional update to the label of Merck's Mevacor to clarify the risk of muscle injury and advise on contraindicated drugs, such as certain HIV treatments.

Dr Amy Egan, deputy director for safety in FDA's division of metabolism and endocrinology products (DMEP), said these warnings shouldn't prevent patients from using the products

She said: “The value of statins in preventing heart disease has been clearly established. Their benefit is indisputable, but they need to be taken with care and knowledge of their side effects.”