Outer ear infection (otitis externa)

Published by Bupa's Health Information Team, October 2010.

This factsheet is for people who have an outer ear infection, or who would like information about it.

Outer ear infection is most common in adults although children can get it as well. The medical term for an outer ear infection is otitis externa. This means inflammation of the outer ear canal (the tube that leads into the ear). It is often caused by an infection.

About outer ear infection

An outer ear infection (known as otitis externa) is sometimes called swimmer's ear as it often develops after you have spent time in water.

An outer ear infection can be acute or chronic. When describing an illness, the terms 'acute' and 'chronic' refer to how long you have had it, not to how serious the condition is. An acute outer ear infection comes on suddenly and goes away within a few weeks. Chronic outer ear infection causes ongoing symptoms that may last several months or keep re-occurring.

Sometimes, a hair follicle at the entrance to your ear canal becomes infected, causing a boil. This is called localised otitis externa. If the infection affects more of your ear canal and reaches your ear drum, this is called widespread or diffuse otitis externa.

Symptoms of outer ear infection

Symptoms of outer ear infection can include:

• pain
• itching
• discharge from the ear
• temporarily dulled hearing - if the swelling is enough to block your ear canal

If you have any of these symptoms, you should see your GP.

Complications of outer ear infection

Infections can become more widespread in the skin (cellulitis) or form a large abscess.

Otitis externa can sometimes progress to a severe infection called malignant otitis. This is when the infection spreads into the bones surrounding the ear, which make up the skull. It is life-threatening without treatment. However, this is rare, and is most likely to occur in people who have problems with their immune system or have diabetes.

If left untreated, an outer ear infection can cause deafness.

Causes of outer ear infection

Outer ear infections are usually caused by bacteria or yeast (fungal infection). Anything that irritates the skin of your ear canal or causes an allergic reaction can also cause inflammation.

You are more likely to develop an outer ear infection if you:

• swim often - this reduces the amount of earwax you have
• swim in contaminated water - this introduces bacteria
• live in a hot, humid climate - the infection is then known as tropical ear
• have a narrow ear canal
• have a skin condition, such as dermatitis or psoriasis - broken skin is more likely to become inflamed
• are sensitive to certain soaps, shampoos or hairsprays - these can irritate the ear canal
• use hearing aids or earplugs - these can irritate the ear canal or introduce bacteria
• damage your ear canal - with a cotton bud, your fingernail, or any other object

Diagnosis of outer ear infection

Your GP will ask about your symptoms and examine you. He or she may also ask you about your medical history.

Your GP may look into your ear using an instrument called an otoscope to check for signs of swelling and infection. Your GP will ask you to move your jaw to see if you feel pain.

If your symptoms don't improve after treatment or they re-occur, your GP may take a sample of the discharge from your ear using a swab. This will be sent to a laboratory for testing.

If you have recurrent outer ear infections, your GP may refer you to an ear, nose and throat (ENT) specialist - a doctor specialising in conditions affecting the ear.

Treatment of outer ear infection

Treatment usually consists of controlling pain and treating the inflammation.

Medicines

The following medicines can help treat symptoms of outer ear infection.

• Painkillers (eg paracetamol or ibuprofen) to relieve pain.
• Antibiotics or antifungals to treat a bacterial or yeast infection. These are usually prescribed as ear drops but your GP make prescribe tablets if you have widespread infection or you are at risk of having a severe infection.
• Steroid-containing ear drops to help reduce itching and swelling in your ear.
• Aluminium acetate ear drops to help to reduce swelling in your ear.
• Acetic acid ear drops to kill some types of bacteria.

Most ear drops will contain a combination of steroids, antibiotics and antifungals and some come in a spray rather than in drop form.

It may be difficult to get ear drops into your ear if your ear is swollen, so your doctor or nurse may apply the treatment using an ear wick. An ear wick is ribbon gauze or a sponge wick, which is placed in your ear and absorbs the drops when they are applied. This allows the ear drops to stay in constant contact with the affected part of your ear. The ear wick is usually left in place for a couple of days, before your doctor or nurse removes it. The ear wick is usually fitted and removed in hospital.

Alternatively, your doctor or nurse may smear a small strip of gauze dressing with antibiotic ointment and gently place it in your ear canal. You may be shown how to remove the dressing yourself.

Prevention of outer ear infection

You can help to prevent an outer ear infection by taking steps to keep your ears dry. For example, if you are a regular swimmer, you can wear silicone ear plugs when you go swimming.

The following tips can help to reduce your risk of having an outer ear infection.

• Don't lie with your head underwater in the bath.
• Put cotton wool smeared with petroleum jelly in your ears before you wash your hair or have a shower.
• Dry your ear with a hair dryer (on the lowest heat setting) after washing your hair.
• Never using cotton buds or other objects to clean your ear canal.
• Never pick your ears with your fingernails.
• Wash your hands before touching your ears.
• Keep hairspray or shampoo away from your ears.
• If you regularly use ear plugs in your workplace, make sure you use a clean pair every day.
• Don't swim in sub-standard swimming pools or contaminated water.

For answers to frequently asked questions on this topic, see Common questions.

For sources and links to further information, see Resources.