Mastoiditis is a serious bacterial infection that affects the mastoid bone behind the ear. It's usually more common in children, although adults can also sometimes be affected.

Symptoms of mastoiditis 

The mastoid bone has a honeycomb-like structure that contains air spaces called mastoid cells. The mastoid cells help maintain the air space in the middle ear.

Mastoiditis can develop if the mastoid cells become infected or inflamed. This is often as a result of a persistent middle ear infection (otitis media). This can cause the porous bone to break down.

Symptoms of mastoiditis typically include:

  • redness, tenderness and pain behind the ear
  • swelling behind the ear that can cause it to stick out
  • discharge from the ear
  • a high temperature, irritability and tiredness
  • headache
  • hearing loss in the affected ear

When to see your GP 

You should see your GP if you or your child has:

  •  any symptoms of mastoiditis
  •  an ear infection that doesn't clear up with treatment or is followed by new symptoms
  •  been diagnosed with mastoiditis and treatment hasn't cleared it up

Causes of mastoiditis

Mastoiditis usually occurs following an untreated middle ear infection. Bacteria from the middle ear can spread to the inner ear, infecting the mastoid cells of the mastoid bone.

cholesteatoma can also cause mastoiditis. This is an abnormal collection of skin cells inside the ear. This may prevent the ear draining properly, leading to infection.

How mastoiditis is diagnosed 

Your GP will examine the inside of the ear with an otoscope (a device with a light and magnifying glass). This is to check for signs of infection or cholesteatoma.

Most ear infections are middle ear infections. If your GP thinks you have mastoiditis as a complication of a middle ear infection, they may refer you to an ear, nose and throat (ENT) specialist.

How mastoiditis is treated 

Mastoiditis is a serious infection and should be treated quickly. It's treated with antibiotics.

Depending on how severe the infection, you may need to go to hospital so that you can be given antibiotics directly into a vein through a drip.

In some cases, surgery may be needed to drain your middle ear (a myringotomy) or to remove part of the mastoid bone (mastoidectomy).


If you've had surgery for mastoiditis, you may need to take time off work. Your doctor will advise you about this.

Take care not to get the affected ear wet. You should be able to wash your hair after about a week, providing you don't get water inside your ear.

You should be able to go swimming around four to six weeks after the operation, depending on how well your ear has healed. Your doctor should be able to advise you at your follow-up appointment.

With early antibiotic treatment, most people with mastoiditis recover quickly and have no complications. However, treatment isn't always easy and the infection may come back.

If the mastoid bone is severely infected and infected bone isn't removed, it can cause hearing loss and life-threatening health complications such as a blood clotmeningitis, or a brain abscess.

The information on this page has been adapted from original content from the NHS website.

For further information see terms and conditions.

This page was reviewed December 2017

This page is due for review May 2020

Health conditions A to Z

Search by health condition or symptoms

Or find conditions beginning with …

Share this page


Your comments are anonymous and can’t be responded to - if you would like a reply, use the feedback form.

Your comments
Plain text only, 750 characters maximum. Don't include personal or financial information.