With prompt treatment, it is possible to cure mastoiditis. Seeking medical care early is important. However, it is difficult for antibiotics to penetrate to the interior of the mastoid process and so it may not be easy to cure the infection; it also may recur. Mastoiditis has many possible complications, all connected to the infection spreading to surrounding structures. Hearing loss is likely, or inflammation of the labyrinth of the inner ear ( labyrinthitis ) may occur, producing vertigo and an ear ringing may develop along with the hearing loss, making it more difficult to communicate. The infection may also spread to the facial nerve (cranial nerve VII), causing facial-nerve palsy , producing weakness or paralysis of some muscles of facial expression, on the same side of the face. Other complications include Bezold's abscess , an abscess (a collection of pus surrounded by inflamed tissue) behind the sternocleidomastoid muscle in the neck, or a subperiosteal abscess , between the periosteum and mastoid bone (resulting in the typical appearance of a protruding ear). Serious complications result if the infection spreads to the brain. These include meningitis (inflammation of the protective membranes surrounding the brain), epidural abscess (abscess between the skull and outer membrane of the brain), dural venous thrombophlebitis (inflammation of the venous structures of the brain), or brain abscess .  
The first-line treatment for arteritis is oral glucocorticoid (steroid) medication, such as prednisone, taken daily for a period of three months.  After this initial phase, the medication may be reduced in dose or frequency, . every other day, if possible.  If the disease worsens with the new treatment schedule, a cytotoxic medication may be given, in addition to the glucocorticoid.  Commonly used cytotoxic agents include azathioprine, methotrexate, or cyclophosphamide.  The dose of glucocorticoid medication may be decreased if response to treatment is good.  This medication may be reduced gradually once the disease becomes inactive, slowly tapering the dose (to allow the body time to adjust) until the medication may be stopped completely.  Conversely, if the disease remains active, the medication will need to be increased.  After six months, if the medication cannot be reduced in frequency to alternate days, or if in 12 months the medications cannot be stopped completely, then treatment is deemed to have failed.