Health A to Z
Otitis externa is a condition that causes inflammation (redness and swelling) of the external ear canal, which is the tube between the outer ear and eardrum.
Otitis externa is often referred to as "swimmer's ear" because repeated exposure to water can make the ear canal more vulnerable to inflammation.
Symptoms of otitis externa include:
Usually only one ear is affected.
With treatment, these symptoms should clear up within a few days. However, some cases can persist for several months or longer.
Read more about the symptoms of otitis externa.
You should see your GP if you may have otitis externa.
Your GP will ask about your symptoms and whether you regularly use any items that are inserted into your ears, such as hearing aids or ear plugs. They may also examine inside your ear using an instrument called an otoscope.
If you have recurring episodes of otitis externa that haven't responded to treatment, your GP may take a swab of the inside of your ear. This will be tested to help determine what type of infection you have, if any, so appropriate medication can be prescribed.
Most cases of otitis externa are caused by a bacterial infection, although the condition can also be caused by:
There are a number of things that can make you more likely to develop otitis externa, including:
Getting water in your ear is particularly significant, because this can cause you to scratch inside your ear, and the moisture also provides an ideal environment for bacteria to grow.
Read more about the causes of otitis externa.
Otitis externa is relatively common. It's estimated that around 1 in 10 people will be affected by it at some point in their lives.
The condition is slightly more common in women than men and is most often diagnosed in adults aged 45 to 75.
People with certain long-term (chronic) conditions are at greater risk of developing the condition. These include:
Otitis externa sometimes gets better without treatment, but it can take several weeks. Your GP can prescribe ear drop medication that usually improves the symptoms within a few days.
There are a number of different types of ear drops that may be used to treat otitis externa, but they all tend to be used several times a day for about a week.
Your GP may refer you to a specialist for further treatment and advice if symptoms are severe or they fail to respond to treatment.
Read more about treating otitis externa.
To help reduce your chances of developing otitis externa, you should avoid inserting cotton wool buds and other things into your ears (including your fingers), as this can damage the sensitive skin in your ear canal.
If you're a regular swimmer, consider using ear plugs when swimming or wearing a swimming cap to cover your ears and protect them from water.
You should also try to avoid getting water, soap or shampoo into your ears when you have a shower or bath.
Read more about preventing otitis externa.
Complications of otitis externa are uncommon, but some can be very serious.
One rare complication of otitis externa is malignant otitis externa, which is where an infection spreads from the ear canal into the surrounding bone.
This requires prompt treatment with antibiotics and sometimes surgery, as it can be fatal if left untreated.
Read more about the complications of otitis externa.
Otitis externa can cause a number of different symptoms affecting the ear and the surrounding area.
Symptoms can include:
Otitis externa sometimes occurs if a hair follicle inside the ear becomes infected by bacteria and develops into a spot (pimple) or boil.
If this happens, you may be able to see the pimple or boil in a mirror. However, don't attempt to squeeze any pimples or boils in your ear, as this could lead to the infection spreading elsewhere.
In some cases, the symptoms of otitis externa can persist for several months, or sometimes years. This is known as chronic otitis externa.
Symptoms of chronic otitis externa can include:
There are several different causes of otitis externa. A number of things can also increase your chance of developing the condition.
Causes of otitis externa can include:
Otitis externa can also return after previous treatment if you don't complete the full course.
The following things aren't direct causes of otitis externa, but may make the condition more likely to develop.
Liquid in your ear canal can make you more likely to develop an infection. Moisture provides an ideal environment for bacteria – and to a lesser degree, fungi – to grow.
Your risk may be increased by:
Water can also wash away earwax inside your ears, which can make them itchy.
Your ear canal is very sensitive and may become damaged through:
Using a hearing aid may also increase your risk of developing otitis externa.
Your chances of getting otitis externa are increased if you use certain products in or near your ears, such as:
As well as seborrhoeic dermatitis, certain underlying skin conditions can increase your risk of otitis externa. These include:
You may be at higher risk of developing otitis externa if you have a condition that can weaken your immune system, such as:
Certain cancer treatments, such as chemotherapy, may also increase your risk of otitis externa.
Otitis externa can usually be treated effectively with ear drops prescribed by your GP and some simple self-care techniques.
In most cases, your symptoms will start to improve within a few days of starting treatment.
If your symptoms are severe or they fail to respond to initial treatment, your GP may refer you to a specialist for further treatment and advice.
The advice below should help to relieve your symptoms to some extent and help to prevent complications:
While otitis externa can clear up by itself, this can take several weeks without treatment. Your GP can usually prescribe medicated ear drops that speed up the healing process. These usually need to be taken several times a day for about a week.
There are four main types of ear drops used to treat otitis externa:
Sometimes you may be given medication that's a combination of the above, such as antibiotic and corticosteroid ear drops.
Once treatment is complete and the inflammation has settled, your doctor may want to re-examine your ear to check for any underlying physical problems that could have contributed to the condition, such as having an abnormal or perforated (torn) ear drum.
Ear drops may not work as well if they're not used in the right way, so it's important to apply them correctly. Ideally, ask somebody else to apply the drops for you, as this makes the process much easier.
You (or your helper) will need to follow these steps:
If necessary, there are some other treatments your GP can provide to help treat otitis externa, such as:
If necessary, your GP may refer you to a specialist for further treatment.
The specialist may decide to remove earwax from inside your ears to help make ear drops more effective. This can be done in a number of ways:
You may also need an ear wick, which is a soft cotton gauze plug covered with medication and inserted into your ear canal.
An ear wick allows the medication to reach the end of your ear canal. It should be changed every two to three days.
Although complications associated with otitis externa are uncommon, there's a small risk of further problems developing.
Some of the main complications of otitis externa are described below.
Abscesses are painful, pus-filled growths that can form in and around the affected ear after an infection.
They usually heal on their own, but in some cases your GP may need to drain the pus from them.
If you have long-term (chronic) otitis externa, thick and dry skin can build up inside your ear canal.
This causes the ear canal to narrow (stenosis), which may affect your hearing and, in rare cases, can even cause deafness. However, it can usually be treated with ear drops.
It's possible for any infection to spread to your eardrum. In some cases, the infection may cause pus to build up inside your inner ear and may rupture (tear) your eardrum. This is known as a perforated eardrum.
In many cases, a perforated eardrum heals without treatment in a couple of months. Surgery may be recommended if it shows no signs of healing after this time.
Cellulitis is a bacterial skin infection that can occur after otitis externa. It's what happens when bacteria that normally live harmlessly on the surface of your skin enter your skin's deeper layers through damaged areas, such as those caused by otitis externa.
Cellulitis causes affected areas of skin to become red, painful, hot and tender to the touch.
Other symptoms include:
Most cases of cellulitis can be treated with a seven-day course of antibiotics.
If cellulitis occurs in a person who was already very ill or who is very vulnerable to the effects of infection, they may need to be admitted to hospital as a precaution.
Malignant otitis externa is a serious, but rare, complication of otitis externa, where the infection spreads to the bone that surrounds your ear canal.
It usually affects adults more than children. Adults who have a weakened immune system are at a particularly increased risk of developing it. This includes people:
There were 442 cases of malignant otitis externa seen in hospitals in England over 2013 and 2014. Most cases were diagnosed in people aged 60 or older.
Signs and symptoms of malignant otitis externa can include:
Without treatment, malignant otitis externa can be fatal. However, it can be effectively treated using antibiotics and surgery to remove any damaged tissue.
It's not always possible to prevent otitis externa, but you can reduce your risk of developing the condition.