I was on bendro many years ago and as its a thiazide diuretic its not a favourite when diabetes is present. If a diuretic is required I would have thought one of the loop catagory ones would be better.
If you are not 100% happy taking it, I would suggest you go back to doc and ask for something different.
Part of my anti hypertensive treatment consists of amlodipine (a calcium channel antagonist) which in part does reduce blood volume by extra peeing, so in its own way is a mild diuretic, but nothing as drastic as the bendro.
I personally think there are far better ways of controlling hypertension than a thiazide diuretic.