What Are Ear Infections? Symptoms, Causes, Diagnosis, Treatment, and Prevention

Ear infections are incredibly common, affecting five out of every six American children by the time they turn 3. (1)

Most of the time, ear infections occur within the middle ear, which is the space behind the eardrum where the ear’s vibrating bones are located. (2) These ear infections are medically referred to as otitis media and can be caused by bacteria or viruses. (3)

When someone complains about dealing with an ear infection, this is usually the type they’re talking about, says Sujana S. Chandrasekhar, MD, a physician with ENT and Allergy Associates in New York City.

Less common are ear infections that occur within the ear canal. These infections are formally known as acute otitis externa, but you likely know them as “swimmer’s ear.” (3) The infections earned that nickname because they commonly occur after swimming. Any water that gets stuck in the ear can harbor bacteria and eventually lead to an infection.

Also infrequent are inner ear infections that occur in the parts of the ear responsible for balance and hearing and sometimes called labyrinthitis, according to MedlinePlus. These infections can cause vertigo — a feeling that the room is spinning — and problems with balance.

Ear infections can be caused by bacteria or viruses and occur when fluid builds up in the middle ear, which is normally filled with air. (2) They are usually accompanied by an ache, which is a result of the area in the middle ear becoming inflamed. The earache may affect one or both ears, but most of the time it’s in one ear.

“Adults describe an ear infection like kidney stones — it can be super painful until it's cleared,” Dr. Chandrasekhar says. It may be dull, sharp, or burning, and it may feel constant or come and go.

The symptoms of ear infections of the middle ear usually occur suddenly. Adults typically will experience ear pain, and they may have trouble hearing or experience fluid draining from the ear. They may also feel dizzy and experience vertigo. (2)

Children with ear infections may experience the same symptoms, as well as: (4)

• Trouble sleeping
• Irritability and being overly fussy
• Loss of appetite because it may be painful to swallow
• Fever up to 104 degrees F
• Tugging at the ear
• Drainage from the ear (not earwax), which could be a sign that the eardrum has ruptured

Signs of infections within the ear canal can include ear redness, swelling, tenderness, and discharge.

Learn More About Signs and Symptoms of Ear Infections

Ear infections are often associated with other illnesses, such as cold and flu viruses or allergies that cause congestion and swelling in the nose and throat. (2) Ear infections are more common in the fall and winter months when there’s an uptick in these illnesses, though people with allergies may see a spike in ear infections whenever pollen counts are high. (2)

To understand what causes ear infections, it helps to know a little about the anatomy of the ear. The eustachian tube goes from the middle of the ear to behind the nasal passage in the back of the throat. When the tube gets clogged — which could be because of swelling, inflammation, or mucus — fluid builds up in the ear and puts pressure on the eardrum. (2,4)

“Therefore, you have a pressure-filled space that’s expanding with no egress,” Chandrasekhar says. “Your ear is like a balloon that’s just about to burst — that kind of pressure.”

The tubes may also get clogged when adenoids, which are pads of tissue located near the beginning of the eustachian tubes in the back of the throat, get inflamed. Swollen adenoids can result in infection. (2)

Children get middle ear infections more often than adults do, with young children between 6 months and 2 years at the highest risk. (2) Middle ear infections are second only to the cold as the most common illness children experience. (4)

The risk of ear infection tapers off as children grow. Younger children are at increased risk; their eustachian tubes are more likely to become clogged because of the anatomy of a child’s ear. The tubes are usually narrower and more horizontal compared with an adult’s ear, and their adenoids are usually larger than an adult’s. Those two factors make it more likely that fluids will get trapped. (2)

Chandrasekhar says the risk of infection lowers when a child’s face shape changes and the tubes become a bit more vertical, usually around age 7 or 8.

Children are also at greater risk because they tend to get more colds and respiratory infections as they’re building up their immune systems, and they may experience ear infections as a result. (4) Children often pass these colds and infections to one another in school or day care settings.

“The transmission of viruses between children is very, very common, so you’ll see kids in day care or houses with very small children having higher rates of ear infection than children who are more apart from other kids,” Chandrasekhar says.

Infants are at increased risk if they drink from a bottle while lying down. (2) “That, as you can imagine, will just pool in the back of the baby’s throat, and the top of the throat is the back of the nose,” which could lead to an ear infection if the fluid gets transmitted to the ear, Chandrasekhar says.

While children are at higher risk for developing ear infections, adults aren’t immune to them. Bad air quality — whether due to pollution or cigarette smoke in the air — can put people of any age at increased risk of developing an infection. (2) “Smoking and secondhand smoke are huge for adults,” Chandrasekhar says.

Certain factors can make someone inherently more likely to develop an infection. There seems to be a hereditary component at play, with ear infections tending to run in families. (3,4)

Some long-term illnesses can also lead to an uptick in ear infections, especially conditions that negatively impact the immune system. (4)

Learn More About Causes of Ear Infections: Common Risk Factors, Genetics, and More

Adults who experience ear pain or fluid drainage from the ear should visit their doctor as soon as possible. Children should visit a doctor if symptoms last longer than 24 hours, the pain is severe and accompanied by discharge, or if the child is younger than 6 months old. (2)

A doctor or nurse will take a look at the ear in question using an otoscope to see whether the eardrum appears swollen or red. They may also blow air at the eardrum using a tool called a pneumatic otoscope. This helps them see whether the eardrum moves. If it does not, it’s likely that there’s fluid in the ear.

Tympanometry, which checks for fluid in the ear using sound and air pressure, may also be used. (4)

Prognosis of Ear Infections

Though sometimes very painful, ear infections usually aren’t a huge cause for concern. But complications can occur.

Some ear infections will require treatment with antibiotics, which can take up to 10 days. (5) In most cases, ear pain subsides without any treatment at all. “For patients over the age of 2, ear infections can be watched for up to 72 hours because the majority of them will resolve on their own if you just manage the pain and let things take their course,” Chandrasekhar says.

If the pain doesn’t go away or is accompanied by other more serious symptoms, you should see a healthcare provider — either your primary care physician or an otolaryngologist, a doctor who specializes in ear, nose, and throat disorders. If your child starts acting sluggish or seems to have a stiff neck, call your doctor immediately. (4)

Ear infections aren’t contagious, and the chances of permanent damage are low. (4) Your doctor may say to wait it out to see if the symptoms clear up without any treatment, which is sometimes referred to as “watchful waiting.” (3,4)

Medication Options

Because ear infections can be painful, the focus of treatment is on managing the pain. (2) Treatment could include over-the-counter painkillers, such as ibuprofen (Advil) and acetaminophen (Tylenol), which generally begin to take effect within an hour or two.

If the wait-and-see approach doesn’t work or the infection is severe, doctors may prescribe antibiotics such as amoxicillin (Amoxil) for 7 to 10 days. (5) Oral antibiotics are usually prescribed for infections in the middle ear, while infections involving the ear canal likely will require antibiotic ear drops. If you have a fever or pain after two days of antibiotics, alert your doctor. (4) Chandrasekhar says it may be necessary to tweak the treatment plan.

It’s important to finish the entire antibiotic treatment prescribed, even if symptoms have cleared up, to ensure the infection doesn’t return. Your doctor will likely want to schedule a follow-up appointment within the month to be sure the infection has been treated successfully. (4)

Some people swear by at-home remedies to treat ear infections, such as applying a warm compress to the infected ear at bedtime when the pain tends to be the most severe. (4) Some of these can offer relief, and Chandrasekhar says it’s okay for older children or adults to give them a try. But they can be risky for children under the age of 2 who are at increased risk of experiencing complications.

Learn More About Home Remedies for Ear Infections

Prevention of Ear Infections

Children and adults can prevent ear infections by:

• Avoiding secondhand smoke
• Keeping allergies under control
• Feeding a baby while holding the bottle at a 45-degree angle to keep fluids from flowing into the eustachian tubes
• Staying up-to-date on a child’s vaccines (3)
• Minimizing the chances of catching a cold
• Breast-feeding babies until they are 1 year old, since breast milk contains antibodies that decrease the risk of infection (3)
• Taking a child to the doctor if he or she exhibits mouth breathing or snoring, which could be a sign of large adenoids (4)

For the most part, there’s no need to worry about complications from ear infections. But they do sometimes occur.

Children who still have fluid in their middle ear after three months may need to have a procedure called myringotomy and tube placement. For this procedure, the doctor will insert tubes through the eardrum in order to balance the pressure between the middle and outer parts of the ear. These tubes fall out on their own, generally after six months to a year.

Very rarely, an ear infection could lead to meningitis or mastoiditis. (4)

Hearing problems may also result from having infections come and go frequently or stick around without fully healing. (2)

If young children experience hearing loss, even temporarily, they may have trouble developing their speech and social skills. (2) “With children who may have other learning disabilities, we are super aggressive about [treating] ear infections,” Chandrasekhar says. “What you don’t need is additional hearing loss, which keeps them from learning properly.”

Learn More About the Complications of Ear Infections: How They Affect Your Body in the Short and Long Term

More than 80 percent of children will have at least one ear infection by the time they turn 3. (5) About 25 percent of children will experience repeated ear infections. (4)

While ear infections are the most common reason for earaches, they’re not the only ones.

Other common causes of earaches include:

• Strep throat
• Sinus infection
• Eczema in the ear canal
• Changes in air pressure, such as when flying on a plane
• Earwax buildup
• A foreign object in the ear
• Use of cotton swabs in the ear
• Shampoo or water trapped in the ear

Less common causes of earaches include:

• Temporomandibular joint (TMJ) syndrome
• Perforated eardrum
• Arthritis affecting the jaw
• Infected tooth
• Impacted tooth
• Braces on teeth
• Trigeminal neuralgia, or chronic facial nerve pain

Centers for Disease Control and Prevention (CDC)

The CDC can help you discover more about the causes and symptoms of ear infections, along with treatment options and prevention tips.

National Institute on Deafness and Other Communication Disorders (NIDCD)

The NIDCD, part of the National Institutes of Health (NIH), conducts and supports research in the normal and disordered processes of hearing, balance, taste, smell, voice, speech, and language.

MedlinePlus

MedlinePlus is a service of the National Library of Medicine (NLM), which is part of the National Institutes of Health (NIH). It offers a wealth of information about ear infections, including related issues.