Many medications in the antibiotic class are compatible with breastfeeding, so don't worry. The important thing here is to treat yourself well. To do this, I recommend that you tell your doctor and pharmacist what medications have been used recently, as well as making sure to do a urine analysis (culture) to determine the bacteria that is causing this problem. Once we have identified the bacteria, we will know which antibiotic could be used. Taking into account your breastfeeding and recent antibiotics, we will select the best choice for you. We look forward to seeing you.