He put you on a loop diuretic?
You need to know the cause of the urinary problems, obstructive, hypertension, diabetes, infection, you need to know this to know the treatment regime
this will make you go pee more, and it will lower your blood pressure a bit, and can cause potassium depletion, as well as calcium magnesium and even sodium, so you have to watch your electrolytes especially given you're not being prescribed this for hypertension