All my pain meds require lots of water... my best suggestion would be to go get your kidneys checked. It is a simple blood test at the doctors and important to have done if you are taking lots of pain meds.
Infections like bladder or kidney? What kind of infections? The pain medications that I have taken has caused bladder infections, yeast infections, kidney stones, and so on.... talk to your doctor because he or she may need to change your prescription.
@A MyFibroTeam Member and @ Pamela Rosser - will do this - it is infections of bladder and kidney