Before using this medication, tell your doctor or pharmacist if you are allergic to it; or to other antibiotics (such as other penicillin’s, cephalosporins); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details. Before using this medication, tell your doctor or pharmacist your medical history, especially of kidney disease. This medication may cause live bacterial vaccines (such as typhoid vaccine) to not work as well. Do not have any immunizations/vaccinations while using this medication unless your doctor tells you to.