A bacterial infection of the parotid gland usually indicates a problem with drainage of the gland, i.
e., an obstruction of the parotid duct inside the mouth. There could be a stone in the duct or gland, just like a gallstone or kidney stone. If antibiotics don't completely resolve it, you should an ENT or oral surgeon for an imaging
study such as a sialogram or a ct to look for an obstruction.