I have a pouch/vagina fistula and, as a result, was getting a number of urinary tract infections. A pharmacist recommended D-Mannose which is just a derivative of cranberry but apparently more effective that cranberry juice. It reportedly keeps the ecoli from attaching to the urethra. I haven't had an infection since I started taking it although I haven't tested going off of it to see. I take one capsule a day. Maybe?