How long can i take azo ( phenazopyridine ) for ?

Need antibiotic: Azo is no substitute for an antibiotic, it is an analgesic for the bladder and helps the symptoms only. You have to get on an antibiotic or the infection can spread to your kidney or blood stream. Azo should be used the first 3 days of antibiotic therapy. After that if still have symptoms, the antibiotic might need to be changed. If you have fever, vomiting, mid back pain, go to the ER.