Actos is a prescription drug used to treat Type 2 diabetes. Studies have linked it with serious side effects and health complications in users. These side effects include a higher risk for congestive heart failure as well as for serious liver problems and bladder cancer. Because of the growing connection between the use of Actos and heart failure, label warnings from the FDA were increased in 2007. Furthermore, a long-term study revealed an increased risk of bladder cancer in Actos users, most especially those who had used it the longest at the highest dosage.

U.S. regulators found in June 2011 that an analysis of a company-sponsored study showed some users of Actos faced an increased risk of developing the potentially fatal disease.

Actos has been linked to an increased risk of heart attack, congestive heart failure, heart disease and death. It has also been linked to an increased risk of bladder cancer, rhabdomyolysis (kidney damage), liver damage, and bone fracture.

A new study conducted by the University of Montreal reviewed records of more than 115,000 British patients "newly treated" with the diabetes drug. The research started in 1988 and ended in 2009. The findings showed that the use of Actos for two or more years could be associated with 88 additional cases of bladder cancer per 100,000 persons. And for patients who took more than 28,000 milligrams of Actos the number of bladder cancer cases rose to 137 additional cases for 100,000.

The study which was published online by the British Medical Journal shows that the risk of bladder cancer associated with Actos is actually higher than the warning the US Federal Food and Drug Administration put out last year.