Folks, I was on this standard diuretic for about 6 years or so. For a very long time, I did not think it was causing any significant side effects (other than having to pee a lot). I was wrong. It gave me type II diabetes.
If you ask MOST doctors and nurses about this, they will deny it strenuously. As one very good PA told me, "diuretics are our first line of defense." An RN just two weeks ago thought I was crazy to blame my diabetes on it.
But it is not my imagination. The ALLHAT study -- which, if you cite, will cause most docs and nurses to shut up right fast -- is one of the most famous studies out there. It was huge, and its authors became strong proponents of diuretics. But the same study found that if you take HCTZ for five years, you have about a 12.6% chance of developing diabetes (versus perhaps a 1 to 2% chance otherwise). I am so angry about this because no one warned me. No one told me this, so I could never make an informed decision about taking this medication. Now I will be fighting diabetes for the rest of my life!
I haven't looked at the insert for HCTZ in a long time, so for all I know they're now finally listing blood sugar issues. But they said nothing when I started in 2002, and no one bothered monitoring by blood sugar either. Even when we finally noticed the glucose readings going up, no one said, "Oh, we should take you off that diuretic."
If you do some googling, you'll discover that there are a (minority) of doctors out there who are also very concerned about this. They argue a lot at forums for doctors. This business about diabetes IS a known side-effect. It's just, as I said, that too few doctors seem to be aware of it, or if they are, seem to feel the need to inform their patients before prescribing it.