Swimmer's ear (otitis externa) is an inflammation and infection of the ear canal . It occurs when the protective film that covers the ear canal (lipid layer) is removed. This causes the ear canal to look red and swollen. The ear canal may be narrower than normal and is tender when the outside of the ear is gently pulled up and back.

Swimmer's ear may develop when water, sand, dirt, or other debris gets into the ear canal. Since it often occurs when excess water enters the ear canal, a common name for this inflammation is "swimmer's ear." If you have had swimmer's ear in the past, you are more likely to get it again.

A rare but serious infection called malignant external otitis can develop if bacteria invade the bones inside the ear canal and spread to the base of the skull. Not many people get this infection-it is mainly seen in older adults who also have diabetes, people who have HIV, and children who have impaired immune systems-but it can be fatal. Symptoms include ear pain with sudden facial paralysis, hoarseness, and throat pain. Antibiotics are used to treat this infection.

Other causes of inflammation or infection of the ear canal include:

• Allergies.
• Bony overgrowths in the ear canal called exostoses.
• Bubble baths, soaps, and shampoos.
• Cleaning the ear canal harshly or with a sharp object.
• Headphones inserted into the ear.
• Scratching the ear canal with a cotton swab, bobby pin, fingernail, or other sharp object.
• Skin problems, such as eczema, psoriasis, or seborrhea.
• Sweating.

Swimmer's ear is more likely if you have a very narrow or hairy ear canal, live in a warm, humid climate, have impacted earwax, or have had a head injury that also injured your ear.

Symptoms can include itching, pain, and a feeling of fullness in the ear. Your ear canal may be swollen. You may have moderate to severe pain, drainage, or hearing loss. Unlike a middle ear infection (acute otitis media), the pain is worse when you chew, press on the "tag" in front of the ear, or wiggle your earlobe.

You may be able to prevent swimmer's ear. Symptoms often get better or go away with home treatment.

Use the Check Your Symptoms section to decide if and when you should see a doctor.