What Is an Ear Infection?

An ear infection occurs when fluid and germs, such as bacteria or viruses, get trapped in the ear and cause inflammation. Ear infections can happen to anyone but are especially common in children. Nearly 90% of children will have at least one ear infection by age 3.

The ear is divided into three sections: the outer ear, middle ear, and inner ear. An infection in the middle ear (otitis media) is the most common.

Colds, sinus infections, and allergies are common causes of ear infections, and can lead to ear pain, fever, difficulty hearing, and pus-like discharge. The body’s immune system can often fight ear infections without treatment, but some ear infections require antibiotics and other medicines to relieve symptoms and clear the infection.

Types of Ear Infection

Different types of ear infections are classified based on which part of the ear is infected. 

Middle Ear Infection (Acute Otitis Media)

A middle ear infection, or acute otitis media, happens when fluid builds behind the eardrum, leading to inflammation and infection.

Middle ear infections are most common in children because their ear structures are smaller than adults' which makes it harder for fluid to drain out of the ear. This is especially true if the ear is blocked or inflamed due to a cold or other illness.

Outer Ear Infection (Otitis Externa)

Also known as swimmer’s ear or otitis externa, outer ear infections affect the ear canal (the part of your ear that extends from your ear opening to your eardrum). Outer ear infections can occur if water remains in the ear after swimming or bathing. Sometimes a scratch on the ear canal or getting something stuck in your ear can lead to an outer ear infection.

Otitis Media with Effusion

Middle ear inflammation can occur when sticky, thick fluid builds up in the middle ear, but no bacterial or viral infection is present. You may feel pressure or fullness in your ear or experience muffled hearing and fluid draining from the ears.

The fluid build up can sometimes lead to a bacterial or viral infection. Most often, however, the fluid will go away without needing treatment.

Ear Infection Symptoms

Ear infections can cause various symptoms, depending on which part of the ear is infected. Common ear infection symptoms include:

• Ear pain, especially when lying down 
• Fluid draining from the ear
• A feeling of pressure or fullness in the ear
• Hearing loss, such as muffled sounds or difficulty hearing in one ear 
• Fever
• Malaise (general feeling of discomfort) 
• Dizziness
• Problems with balance 

Infants and young children who cannot communicate how they're feeling may pull or tug on their ears, be fussy or irritable, have difficulty sleeping, and have less energy than usual.

What Causes Ear Infections? 

When bacteria or viruses enter the ear, they can cause inflammation and fluid buildup which leads to an ear infection. There are different causes of ear infections, depending on which part of your ear is affected.

Middle Ear Infection Causes 

A middle ear infection occurs when fluid and germs (bacteria) accumulate behind the eardrum. The fluid buildup is often the result of a blocked or swollen eustachian tube, which connects the middle ear to the back of the nose.

The eustachian tube helps regulate air pressure in the ear and drains fluid in the middle ear. When the tube becomes blocked or swollen, it can lead to fluid buildup and increase the risk of infection. Common causes of middle ear infections include:

• Common cold 
• Sinus infection
• Allergies 
• Excess mucus and saliva production, especially in teething infants 
• Infected or enlarged adenoids (lymph tissue between the back of your nose and throat)
• Smoking 
  

Certain factors can increase your risk of developing a middle ear infection, including:

• Attending daycare 
• Changes in climate or altitude 
• Recent illness (cold, flu) 
• Family history of ear infection

Outer Ear Infection Causes

Outer ear infections usually happen when bacteria infect the skin of the ear canal. The ear canal is a narrow, tube-like structure that extends from the outer ear to the eardrum. When the skin inside the ear canal is damaged or irritated, it can create an environment where bacteria can thrive and cause an infection.

Common causes of outer ear infections include:

• Getting excessive moisture in the ear from swimming, bathing, or sweating
• Scratching or injuring the skin inside the ear canal
• Cleaning the ear canal with cotton swabs, which can damage the skin and push wax deeper into the ear canal
• Using earbuds or hearing aids, which can irritate the skin inside the ear canal
  

Risk factors for outer ear infections include:

• Having a narrow or hairy ear canal, which can trap bacteria and viruses in the ear canal 
• Living in a warm, humid climate 
• Swimming frequently
• Having skin conditions such as psoriasis or eczema, which can make the skin more prone to infection
  

How Is an Ear Infection Diagnosed?  

A healthcare provider will diagnose an ear infection through a physical exam, medical history and symptom evaluation, and diagnostic tests.

During the physical exam, your healthcare provider will look inside your ear using an otoscope—a small handheld device with a light and magnifying lens—to look for redness, swelling, and fluid buildup in the ear. They will ask about your symptoms and medical history, including whether you have had previous ear infections.

A physical exam is often enough to diagnose an ear infection. Sometimes diagnostic tests are used to confirm the diagnosis:

• Tympanometry: A small probe sends sound waves into the ear to measure how well the eardrum vibrates in response to changes in air pressure. This test can help determine if there is fluid in the middle ear.
• Audiometry: A hearing test measures your ability to hear sounds at different frequencies and volumes. This test can help determine if there is any hearing loss due to the infection.
• Imaging tests: If your healthcare provider suspects a structural abnormality is causing the infection, or you have signs of infection-related complications, they may suggest an imaging test. A computed tomography (CT) scan or magnetic resonance imaging (MRI) test can provide a more detailed view of the ear and surrounding structures.

Treatments for Ear Infection  

The body’s immune system can often fight an ear infection without treatment. If symptoms persist for over three days, medication can help alleviate symptoms and eliminate the infection.

Treatment options for ear infections may include:

• Antibiotics: Bacterial ear infections are often treated with antibiotics such as amoxicillin (Augmentin).
• Pain relievers: Over-the-counter pain relievers, such as acetaminophen (Tylenol) or ibuprofen (Advil), can help relieve pain and reduce fever. 
• Ear drops: Over-the-counter or prescription ear drops may help relieve pain and inflammation in the ear. These drops may contain a combination of anesthetic, antibiotic, and steroid medications.
• Surgery: Surgery can help drain fluid from the middle ear and prevent recurrent ear infections. The procedure, a myringotomy, involves inserting tiny tubes into the eardrums, which allows air and fluids to drain easily from the middle ear.

How to Prevent Ear Infection 

It is not always possible to prevent an ear infection, but there are some measures you can take to potentially reduce the risk of developing an infection:

• Wash your hands frequently to prevent the common cold and other respiratory infections
• Avoid smoking and exposure to secondhand smoke
• Keep immunizations up to date, particularly those for the flu and pneumonia
• Breastfeed your baby; breastmilk has antibodies that protect against ear infections
• Keep your baby’s head elevated when drinking from a bottle 
• Manage allergies with effective treatments and avoid exposure to allergens 
• Dry your ears after swimming, showering, or bathing
• Avoid putting items inside your ear canal, including cotton swabs

Complications 

Most ear infections get better with time and treatment. Complications can occur if an ear infection is left untreated, such as:

• Hearing loss: Frequent ear infections can increase the risk of damaging the ear and result in long-lasting hearing loss.
• Speech or developmental delays: Young children with frequent ear infections may experience speech or developmental milestone delays due to hearing loss.
• Perforated eardrum: Fluid and pus buildup behind the eardrum can lead to rupture, leaving a hole in the eardrum.
• Mastoiditis: This is a rare, severe complication of middle ear infections in which the infection spreads to the mastoid bone behind the ear, causing pain and inflammation.
• Meningitis: In rare cases, severe ear infections can lead to meningitis, a potentially life-threatening brain and spinal cord infection.
• Cholesteatoma: Frequent ear infections can cause abnormal growth of skin cells behind the ear drum, damaging the delicate bones and structures inside the ear. 
• Facial paralysis: Swelling associated with an ear infection can compress the facial nerve responsible for controlling facial expressions. 

Living With an Ear Infection  

Coping with the pain and discomfort of an ear infection, whether your own or your child’s, can be a struggle. Fortunately, most ear infections go away on their own within 2 to 3 days.

If your healthcare provider prescribes antibiotics to treat an ear infection, you should start to feel better within a couple of days. Continue taking the entire course of your medicine to ensure the infection completely heals. 

In the meantime, consider these coping strategies to help you feel better while you wait for your ear infection to clear up: 

• Use over-the-counter pain relievers to alleviate pain and reduce a fever 
• Apply a warm, dry compress to the affected ear to soothe pain and discomfort 
• Take time off work or school to rest and promote healing
• Drink plenty of fluids, such as water and herbal tea, to support your immune system
• Avoid irritants such as cigarette smoke
• Seek support from a family member or friend to help you cope with the stress and frustration of dealing with an ear infection 
  

Remember to follow your healthcare provider’s instructions regarding treatment and follow-up care to help prevent complications and promote a speedy recovery.