An ear infection is an infection or inflammatory process affecting part of the ear, most commonly the outer ear canal or middle ear. The term therefore covers several clinically different conditions rather than one single disease. Otitis externa affects the skin lining the external ear canal and is often associated with water exposure, local irritation or skin conditions.
Otitis media affects the air-filled middle-ear space behind the eardrum and commonly follows a cold or other upper respiratory infection, particularly in children. Less commonly, infection can involve deeper structures of the ear. The cause, symptoms and treatment therefore depend on which anatomical part is affected. NHS guidance states that ear infections are very common, particularly in children, and that many resolve without specific treatment.
Middle-ear infections frequently occur after respiratory infections because inflammation and congestion can impair the Eustachian tube, the passage connecting the middle ear with the back of the nose and throat. The tube normally helps equalise pressure and allows fluid to drain from the middle ear. During a cold, swelling can obstruct this pathway, allowing fluid to accumulate behind the eardrum and creating conditions in which microorganisms can proliferate. Viral infections are common causes, and bacterial infection can occur as well. Children are particularly susceptible because their Eustachian tubes are anatomically shorter and more horizontal than in adults. This helps explain why ear infections are much more common during childhood.
Outer-ear infection, or otitis externa, has a different mechanism. Moisture trapped in the ear canal, especially after swimming, can alter the local environment and damage the protective skin barrier. Bacteria can then multiply and cause inflammation of the canal. Mechanical trauma from cotton buds, fingers or other objects can also damage the skin and facilitate infection. Eczema and other dermatological conditions can weaken the barrier and predispose to recurrent otitis externa. Symptoms may include ear pain, itching and irritation around or inside the canal, discharge and sometimes reduced hearing because swelling or debris blocks the canal. Avoiding unnecessary manipulation and keeping the canal appropriately dry can therefore help prevent this type of infection.
Typical symptoms of an ear infection include earache, a feeling of pressure or fullness, reduced hearing, fever and sometimes discharge from the ear. Outer-ear infection often causes prominent itching and tenderness when the external ear or canal is touched, while middle-ear infection more commonly produces deep ear pain and pressure associated with a preceding respiratory illness.
Young children may not be able to describe ear pain and may instead pull or rub the affected ear, become irritable, sleep poorly, eat less or fail to respond normally to sounds. Balance problems can also occur. NHS guidance lists pain, high temperature, difficulty hearing, discharge, pressure or fullness, itching and irritation among possible symptoms.
Many uncomplicated ear infections improve without antibiotics. NHS guidance states that ear infections often get better on their own within about three days, although symptoms can sometimes persist for up to a week. Management may therefore initially focus on pain control and observation when there are no features requiring immediate treatment. Paracetamol or ibuprofen can be used where appropriate, taking age, dosage, contraindications and other medicines into account. Children under 16 should not be given aspirin. Antibiotics are not automatically necessary because many infections are viral or resolve without antimicrobial therapy, and unnecessary antibiotic use contributes to antimicrobial resistance and can cause adverse effects.
Treatment depends on the anatomical site and cause. Bacterial middle-ear infections may sometimes be treated with antibiotic tablets when clinical circumstances warrant them. Otitis externa may require antibiotic, antifungal or steroid-containing eardrops depending on the organism and inflammatory process. Pain-relieving eardrops may also be used in selected cases. If a boil or abscess occurs in the ear canal, drainage may sometimes be required. Correct administration of eardrops is important because drops need to reach the affected canal and may not work adequately if debris obstructs the pathway. Decongestants and antihistamines are not routinely useful for ordinary ear infections, and NHS guidance specifically states that there is no evidence they help.
Ear infections should be distinguished from other causes of ear pain and hearing problems. Earwax blockage can cause fullness and reduced hearing without infection. Dental disease, temporomandibular joint disorders, throat infections and referred pain can produce earache even when the ear itself is normal. A perforated eardrum can cause discharge and hearing changes and may occur with or after an infection.
Mastoiditis, in which infection spreads to the bone behind the ear, is an uncommon but serious complication requiring urgent medical treatment. Severe systemic illness, swelling around or behind the ear, significant hearing loss, persistent discharge or symptoms that are not improving should therefore receive appropriate medical assessment rather than being treated as an uncomplicated ear infection.
Prevention differs according to the type of infection. Childhood vaccination reduces the risk of several infections that can contribute to middle-ear disease, while avoiding exposure to cigarette smoke can reduce respiratory and ear-related risks in children. Objects such as cotton buds and fingers should not be inserted into the ear canal because they can damage the skin and remove protective earwax.
People prone to otitis externa can reduce risk by keeping excessive water out of the ear during swimming or bathing, using suitable earplugs or a swimming cap where appropriate and treating underlying eczema or other skin conditions. NHS guidance specifically recommends avoiding cotton buds or fingers in the ears, limiting exposure to smoky environments for children and taking practical measures to reduce water entering susceptible ears.
