Hi I am on the same antibiotics because of a kidney infection 2nd one in a year and iv just come to the end of it and I have what I'm guessing is an ulcer the size of America, ok exaggerating but it's so sore I can't eat drink and it's just seems to get bigger. I have also been researching and it's not good to take ibrufen(spelt it wrong) as it can prolong a kidney infection but my doctor told me to take it to ease the pain of the uti. I don't know where to turn but I agree the antibiotics are a relief to the pain I was in. How are you feeling now?