What are the possible issues you could run into if you use uristat (phenazopyridine) for longer than intended?

Uristat, (phenazopyridine) or..: ..phenazopyridine hydrochloride exerts pain-killing/ analgesic effects on the lining of the urinary tract/bladder. Its precise mechanism is not well-understood. It is used for short term relief of urgency, burning and urinary pain. There have been reports of serious side effects when not taken as directed: liver toxicity, red blood cell destruction, and kidney failure. TAKE AS DIRECTED! Stay well!