Metformin and Bladder Tumors?

Has anyone been prescribed metformin then within a short time frame had blood in the urine and discovered they have tumor in their bladder?

Hi Jen, I did a little online research. The answer to your question us yes.

A search of ‘metformin bladder cancer’ has a lot of information (by people marketing metformin) that metformin can reduce the risk if bladder cancer.

However, there was one very large scientific review showing metformin does not reduce bladder cancer in type 2 diabetes.

That said, truthfully, metformin has a bunch if side effects including kidney problems that are particularly predominant in elderly patients. For this reason, metformin is contraindicated for elderly patients or patients with impaired kidney function.

Since kidney function is closely related to bladder, it would be expected that metformin would also cause bladder problems.

Your situation if a diagnosis of bladder tumors a short time after starting metformin is disturbing and your conclusion is valid, I think. Its unfortunate that really, there is no system to document the occurrences of side effects from medications within the medical system. So cases such as yours go undocumented. Keep in mind, the liability associated with drug side effects would discourage doctors from reporting their findings even if there were a way to report them.

A further search of ‘metformin class action lawsuits’ indicates a ton of people have contracted bladder cancer in association with type 2 diabetes drugs, including metformin.

I’d get yourself a lawyer. I look after my elderly mother and have had amazing success with diet, herbs and acupuncture. I was able to get her completely off meds in less than 6 months.

Hi Mtviewcat,

Thank you for your reply, it is really appreciated.

It is my hubby this had happened to, he was prescribed metformin in february after a heart attack. He has never had any symptoms of diabetes, one nurse said, glucose can rise after a heart attack, which lasts about 3 months but, every other person I have mentioned this to in the medical profession look at me blank and say no, it does not happen.

The doctor kept saying smoking causes it but, even he did not really believe this to be the cause when we said, he had not smoked for 44 years.

I really believe it is caused by the metformin, I will mention this at our next appointment, I will not let it go until I find answers.

there is a very established method of reporting any suspected adverse drug reaction!

Was he also on pioglitazone or rosiglitazone (now withdrawn)? these are known to increase risk/cause bladder cancer. And in smokers that’s more a likely explanation than Metformin.

No he was only on Metformin, as there has never been a study it is hard to find cases but, I did find three people who said they had developed bladder tumor all within 6 months from first taking Metformin. He is off it now but that does not cure the tumor.