List of products in the National Drug Code with proprietary name . This medication is used with other medications to treat tuberculosis (TB). In some cases, it may also be used to treat urinary tract infections (UTIs). It works by stopping the growth of bacteria. This antibiotic treats only bacterial infections. It will not work for viral infections (such as common cold, flu). Using any antibiotic when it is not needed can cause it to not work for future infections.