An analysis of adverse events reported to the Food and Drug Administration has uncovered 11 deaths due to liver toxicity among patients taking the diabetes drug Avandia. The consumers group Public Citizen, which conducted the analysis, estimates that because few side effects cases are reported to the FDA, the actual number of patients who developed liver failure after using Avandia could be much higher.

Avandia has been the subject of previous health concerns due to a potential increased risk for causing heart attacks and heart failure. In May 2007, the New England Journal of Medicine published a study which found that patients taking Avandia had an increased risk of heart attacks or death due to cardiovascular problems. The study found that Avandia users were 64% more likely to die due to heart problems and 43% more likely to suffer a heart attack than patients who were given another drug or a placebo.

Public Citizen’s study also uncovered 10 cases of liver failure linked to the diabetes drug Actos. Actos has also been linked to an increased risk of heart failure.