Photo of children in swimming caps at a swimming pool (PantherMedia / benis arapovic)

A red and swollen outer ear canal is a typical sign of an inflammation, also called otitis externa. Outer ear infections are among the most common causes of earache. They are often caused by bacteria. But fungi, viruses or allergies are sometimes to blame too.

The outer ear is the part of the ear from the eardrum to the fleshy part that you can see (the auricle). The outer ear canal (external auditory canal) leads from the eardrum to the auricle. The medical term for outer ear infections is "otitis externa." "Otitis" is the Latin word for inflammation of the ear.


If you have otitis externa, your ear may hurt or feel uncomfortable – especially when you touch or pull on it. Itching is common too.

The skin in the ear canal is red and swollen, and sometimes also flakes or oozes a liquid. The ear might then become blocked, making it difficult to hear properly.

In about 1 out of 3 people the symptoms are so severe that it affects their everyday lives. About 1 out of 5 people have to stay home from work or school for a few days because of the infection.

Causes and risk factors

Outer ear infections are usually caused by bacteria, but they might also be caused by a fungal infection, for example a yeast fungus. Sometimes viral illnesses, such as the flu or a certain type of shingles (Zoster oticus), lead to outer ear infections too. And sometimes allergic reactions – for instance, to a shampoo – are to blame.

Outer ear infections are also often called "swimmer's ear" because germs can easily get into the ear canal while you're swimming. This means that people who swim a lot are more likely to get outer ear infections. Minor injuries to the ear – for instance, through the use of cotton ear buds to clean your ear, or regularly wearing headphones that you stick inside your ear ("in-ear headphones") – can increase the risk too. People who have already had an outer ear infection or are generally susceptible to infections are also more likely to get (more) outer ear infections.

Prevalence and outlook

Outer ear infections are common: About 1 out of 10 people will have one at some point in their life.

The infection is usually mild and clears up on its own after a few days or weeks. But it sometimes lasts longer. In rare cases it may spread to nearby tissue.


In order to prevent outer ear infections, it's important not to irritate or damage the ear canal. Pointed objects shouldn't be inserted into the ear canal. But simply trying to clean your ears with cotton ear buds can cause damage to the ear canal too. There's no need to use cotton ear buds anyway because your ears clean themselves by producing earwax. When the earwax comes out of your ears, you can remove it (and the dirt inside it) with a tissue. If larger amounts build up or a hard "plug" develops, the earwax can be softened, for instance with olive oil, allowing it to leave the ear more easily. It's important to take care, though. If you are unsure, it might be better to get a doctor to flush out your ear and remove the built-up earwax.

The following things can also help prevent outer ear infections:

  • A snug-fitting swimming cap can help keep water out of your ears while swimming, showering or taking a bath.
  • People who use ear plugs while swimming should make sure that they are soft and fit properly.
  • If water does get into your ear, you usually just need to tilt your head to the side to let the water flow out. Gently pulling your earlobe and jumping up and down a little can help.
  • If you have sensitive ear canals, don't use ear plugs to protect your ears from noise, dust or water too often. The same is true for in-ear headphones. You could try other kinds of headphones instead.

If you have noticed that certain shampoos, soaps or other cosmetic products lead to ear infections, it's best to use other products instead.

Research summaries


The medications that are commonly used to treat outer ear infections include painkillers and disinfectant ear drops or sprays. These are available from pharmacies without a prescription. Acute outer ear infections that are caused by bacteria are often treated using special ear drops that have to be prescribed by a doctor.

If the inflammation is severe or lasts for several weeks, your doctor might place a little sponge or a strip of gauze soaked in ear drop fluid into your ear canal. Sometimes other kinds of medication are needed too – for instance, if the ear infection was caused by shingles.

Research summaries

Further information

When people are ill or need medical advice, they usually go to see their family doctor first. Read about how to find the right doctor, how to prepare for the appointment and what to remember.