Welcome and thanks for your question. Hydrochlorothiazide is a simple diuretic that works by helping remove excess fluids from your blood and tissues. It is very safe and can be discontinued anytime, but preferably after you have made the necessary lifestyle changes to lower your BP.
Also, I have never heard of Paxil causing HP, but [perhaps some one else has.
I hope this helps,
I looked at a couple of websites for paxil side effects and didn't see hypertension listed on any of them.
Before discontinuing any medication you should check with your doctor but it's my understanding that diuretics are not meds that need to be tapered or have a rebound effect if stopped at any time.