Mastoiditis

Medically Reviewed by Shruthi N, MD on February 10, 2026

Mastoiditis is a bacterial infection that affects part of your temporal bone, the big bone behind your ear. It starts as a middle ear infection. Anyone can get mastoiditis, but children younger than 2 years are most vulnerable.

It used to be a common cause of death in very young children. Now it's a rare condition thanks to vaccines (which prevent infections) and antibiotics.

What Causes Mastoiditis?

It most often happens when a middle ear infection goes untreated and spreads to the nearby bone. Mastoiditis can happen without a middle ear infection, but it's rare. That's when you have an abnormal skin growth called cholesteatoma in your middle ear. It can block fluid from draining from your middle ear and lead to mastoiditis.

Mastoiditis Risk and Prevention

The best thing you can do to prevent mastoiditis is get ear infections treated quickly. You can also help prevent this infection by:

Limiting the use of pacifiers
Avoiding secondhand smoke
Controlling any allergies
Vaccinating your child with the pneumococcal vaccine
Protecting your child from common colds

What Are the Symptoms of Mastoiditis?

They may include:

Fever, irritability, and lethargy
Swelling of the earlobe
Redness and tenderness behind the ear
Drainage from the ear
Bulging and drooping of the ear

Mastoiditis Complications

Without treatment, mastoiditis can spread in your body and cause complications such as:

Facial paralysis
Nausea, vomiting, vertigo (labyrinthitis)
Hearing loss
Brain abscess or meningitis
Vision changes or headaches (blood clots in the brain)

Serious complications are less common than they used to be, but it's important to get treatment quickly to avoid long-term problems.

How Is Mastoiditis Diagnosed?

Your doctor will look in your ear with an otoscope. They may also do some tests, such as:

Blood tests to look for signs of infection
An ear culture to look at the drainage from your ear
A CT scan to find the location of your infection.
An MRI test to see the area between your ear and your brain

How Is Mastoiditis Treated?

When you or your child is diagnosed with acute mastoiditis, you may receive treatment from a doctor who specializes in ear, nose, and throat disorders, also called an otolaryngologist. They'll determine the treatment best suited for you, which usually includes antibiotics and steroids.

Antibiotic therapy

Antibiotics are the standard treatment for acute and chronic mastoiditis. You may get antibiotics through an IV line.

Surgery

In some cases, surgery may be needed to drain fluid from your middle ear. In this procedure, called a myringotomy, your doctor makes a small hole in your eardrum to drain fluid and relieve pressure from your middle ear. A small tube may be inserted into your middle ear to keep the hole from closing, allowing for continued drainage. The tube usually falls out on its own after 6-12 months.

If your symptoms don't quickly improve on IV antibiotics or you get complications like an abscess or bone erosion, your doctor may suggest surgery to remove the infected mastoid bone. This is called a mastoidectomy.

How is chronic mastoiditis treated?

It's treated with oral antibiotics, eardrops, and regular ear cleanings by a doctor. If these treatments don't work, surgery may be needed to prevent further complications.

Is Mastoiditis Serious?

It can be, if not treated. Life-threatening complications from mastoiditis are less common than they once were. But it can spread to other parts of your body and cause:

Facial paralysis
Complete or partial deafness
Meningitis (infection of the lining of your brain)
Encephalitis (swelling in your brain)
Sepsis (life-threatening infection)

Takeaways

Mastoiditis is an infection of part of your temporal bone, the large bone behind your ear. It happens when middle ear infections spread to that area. Symptoms include ear pain, drainage, and trouble hearing. Treatments include antibiotics, steroids, and draining the infected middle ear fluid. Serious cases may need surgery. It's important to treat mastoiditis quickly, before it spreads to other parts of your body and causes long-term issues.