By Natasha Persaud

People taking pioglitazone (Actos) for diabetes may have higher odds of developing bladder cancer, suggests an observational study in BMJ. Taking pioglitazone for more than two years appeared to double the risk for the rare cancer, and consuming cumulative dosages of more than 28,000 mg increased the risk by more than two and a half times.

Bladder Cancer - Johns Hopkins Medicine

By comparison, rosiglitazone (Avandia) users had no increased risk. Rosiglitazone is another medication in the same drug class, thiazolidinediones, which decrease the body's resistance to the actions of insulin. In 2010, the FDA restricted Avandia use due to concerns over increased heart attack risk.

In this study, more people developed bladder cancer than would be expected in the general population, but the actual number of cases was still relatively low.

This year about 56,000 men and 18,000 women will be diagnosed with bladder cancer in the United States, according to the National Cancer Institute. Most will be over 70 years old. Smoking tobacco is the most important risk factor to avoid.

Should You Take Pioglitazone (Actos)?

In August 2011, the FDA updated pioglitazone medication labels to reflect a possible increased risk of bladder cancer. Healthcare professionals were urged not to start pioglitazone in patients with active bladder cancer. They were also asked to exercise caution when using the medications in patients with a prior history of bladder cancer.

If you are taking pioglitazone (Actos) to manage diabetes or considering it, talk to your doctor about the risks and benefits of using the glucose-lowering drug.


Azoulay, L. “The use of pioglitazone and the risk of bladder cancer in people with type 2 diabetes: nested case-control study.” BMJ, May 31, 2012.


National Cancer Institute of the National Institutes of Health

Publication Review By: the Editorial Staff at

Published: 04 Jun 2012

Last Modified: 11 Sep 2015