What Causes Recurring UTIs In An Elderly Person?

My Mom is 78 , in a rural area with questionable quality of medical care, frankly. She has recurrent UTIs, currently on Cipro with no improvement ( and 4 days to get a reply from office after calling repeatedly with symptoms and then no culture done when she finally had a u/a!) Has an appt on Thursday 4/2 with NP. At one time she did well on a drug prescribed by a urologist that she took 3 x a week for several months. Can you tell me what that drug probably was so I can suggest to NP? Unfortunately in these rural areas, you tend to have to do your own research.