B.M.
I would always call my sons pediatrician if I was given a prescription while breast-feeding. They will know if it's safe, and it only takes a minute to call the office. This won't help the bacterial infection, but when I was nursing, and had some issues with yeast infections, I heard to take acidophilus and it cleared the infection right up. My nurse at my OB said acidophilus doesn't work, but I tried it anyway, and it really did work... it was nice to breast-feed pain free again!