Bacterial Infection

Bacterial infection is a common cause of acute otitis externa. Bacteria frequently associated with the condition include:

• Pseudomonas aeruginosa, which is commonly found in moist environments.
• Staphylococcus aureus, which may be present on the skin and can cause infection when the skin barrier is damaged.

When bacteria multiply inside the ear canal, they may cause swelling, redness, pain, and discharge from the ear.

Fungal Infection

Certain fungi, including Aspergillus and Candida, can cause infections of the external ear canal, particularly when moisture remains trapped inside the ear or when the normal balance of microorganisms in the ear canal has been disrupted.

People with fungal infections may experience significant itching, a blocked sensation in the ear, or abnormal discharge.

Water Trapped in the Ear Canal

Swimming, bathing, and other activities that repeatedly expose the ears to water can cause moisture to remain inside the ear canal.

Persistent moisture may interfere with the protective function of the skin and earwax, making the ear canal more susceptible to inflammation and infection.

Ear Picking or Aggressive Ear Cleaning

Using cotton swabs, hairpins, or other objects inside the ear canal may cause small scratches or injuries to the skin.

These injuries can provide an entry point for microorganisms and increase the risk of infection. Cleaning the ears too frequently may also remove earwax, which plays an important role in protecting the ear canal naturally.

Skin Conditions and Irritation

People with certain skin conditions may have an increased risk of developing otitis externa, including:

• Eczema
• Psoriasis
• Contact dermatitis

These conditions can make the skin inside the ear canal more sensitive to irritation and may weaken its natural protective barrier against infection.

Severe swelling and blockage of the ear canal

Significant inflammation can cause the ear canal to narrow or become blocked, potentially resulting in temporary hearing loss or a blocked sensation.

Infection spreading to surrounding tissues

In some cases, infection may spread beyond the ear canal and cause redness, swelling, or pain involving the outer ear and surrounding skin.

Severe infection involving the skull base

This condition, known as necrotizing otitis externa, is an uncommon but serious complication in which the infection can spread to the bone around the base of the skull.

It occurs more frequently in people with diabetes, particularly when blood glucose levels are poorly controlled, and in people with weakened immune systems. People in these higher-risk groups should seek medical evaluation promptly if they develop symptoms suggestive of an ear infection.

Medical History

The doctor may ask about symptoms such as ear pain and itching, when the symptoms began, recent swimming or water exposure, ear-cleaning habits, and underlying medical conditions.

Examination with an Otoscope

An otoscope may be used to examine the ear canal and eardrum for abnormalities such as:

• Redness and swelling of the ear canal
• Discharge or pus
• Blockage of the ear canal
• Abnormalities of the eardrum

This examination can also help distinguish otitis externa from middle ear infections and other ear conditions.

Additional Tests

For severe, recurrent, or treatment-resistant infections, a sample of ear discharge may be collected to identify the microorganism responsible. If the infection is suspected to have spread into surrounding tissues or bone, additional imaging tests may be considered as appropriate.

Ear Drops

Ear drops are the main treatment for uncomplicated acute otitis externa. Depending on the cause and clinical findings, a doctor may prescribe:

• Antibiotic ear drops for bacterial infections
• Ear drops containing anti-inflammatory medication
• Antifungal ear drops when a fungal infection is suspected or confirmed
• Other types of ear drops depending on the underlying cause and severity

The choice of medication must also take the condition of the eardrum into consideration because some ear drops may not be suitable for people with a perforated eardrum. For this reason, ear drops should not be used without appropriate advice from a doctor or pharmacist.

Pain Relief

For people experiencing ear pain, appropriate pain-relieving medication may be recommended based on age, underlying medical conditions, and individual precautions.

Cleaning the Ear Canal

If discharge, debris, or dead skin has accumulated inside the ear canal, a healthcare professional may clean the canal using an appropriate technique. When severe swelling prevents ear drops from reaching the affected area effectively, a device may sometimes be used to help deliver medication deeper into the ear canal.

Oral Antibiotics

Oral antibiotics are generally not necessary for uncomplicated otitis externa. However, if the infection has spread beyond the ear canal or the patient has certain risk factors, a doctor may prescribe oral or intravenous antibiotics when clinically appropriate. Patients should use medications exactly as prescribed and should not stop or change their treatment without medical advice.

Keep the affected ear dry

Avoid swimming while symptoms are present and take care to prevent water or shampoo from entering the ear during bathing.

Do not insert cotton swabs or other objects into the ear

Ear picking or cleaning may cause additional injury to already inflamed skin and increase the risk of infection.

Use ear drops as directed

If ear drops have been prescribed, use them according to the recommended dose and duration to help ensure effective treatment.

Avoid devices that irritate the ear canal

Avoid using in-ear headphones or other devices that come into contact with the ear canal if they cause pain or irritation.

Do not put unapproved liquids or substances into the ear

Avoid putting oils, alcohol, vinegar, or other substances into the ear without medical advice, particularly when the condition of the eardrum is unknown.

Dry the Ears After Water Exposure

After swimming or bathing, tilt the head so that each ear faces downward to allow trapped water to drain naturally. A clean towel may be used to gently dry the outer ear, but it should not be inserted into the ear canal.

Avoid Ear Picking

Earwax helps protect the skin inside the ear canal from dirt and certain microorganisms. Removing earwax unnecessarily may interfere with this natural protective mechanism.

Use Appropriate Water Protection

People who swim regularly may consider using properly fitted ear protection that helps prevent water from entering the ear without causing irritation.

Keep Ear Devices Clean

Hearing aids and other devices that come into contact with the ear canal should be kept clean. Their use should be limited if they cause irritation.

Manage Underlying Skin Conditions

People with eczema, psoriasis, or other skin conditions affecting the ear canal should receive appropriate treatment to help reduce inflammation and the risk of recurrent otitis externa.