Otitis externa is a condition that causes inflammation (swelling) of the external ear canal. This is the tube between the outer ear and eardrum (tympanic membrane).
Otitis externa is sometimes called ‘swimmer's ear’ or ‘tropical ear’. This is because it can sometimes be caused by getting water inside your ear canal and it is often more common in humid conditions.
Otitis externa can also be caused by an infection or an allergic reaction to something that comes into contact with the external ear canal. In many cases of otitis externa, the cause is unknown.
How common is otitis externa?
Each year in the UK, otitis externa affects around 1% of the population. Although anyone can get otitis externa, it is slightly more common in women than in men.
People with certain chronic (long-term) conditions are at greater risk of developing otitis externa. Such conditions include:
eczema (a skin condition)
asthma (a condition that causes the airways to become inflamed, making breathing difficult)
allergic rhinitis (a condition where an allergic reaction causes the inside of your nose to become inflamed)
Otitis externa can be easily treated with eardrops and analgesics (painkillers). However, in rare cases, complications can develop, such as the formation of abscesses (pus-filled growths), which can form in and around your affected ear, and cellulitis (a bacterial infection). See Otitis externa - complications for more details.
There are a number of simple measures that may prevent otitis externa from recurring. See Otitis externa - prevention for more information.
Last updated: 21 February 2013
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