What Is Ear Infection? Symptoms, Causes, Treatment, and Medications

An ear infection develops when bacteria or viruses infect the middle ear, usually after fluid becomes trapped behind the eardrum. Most cases follow a viral upper respiratory infection that swells and blocks the eustachian tube.

Common causes and contributors include:

Infections and Anatomy

• Recent cold, flu, sinus infection, or sore throat
• Blocked or swollen eustachian tubes that cannot drain fluid
• Bacteria such as Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis
• Viruses, including cold and influenza viruses
• Allergies that cause nasal and eustachian tube swelling

Risk Factors in Children

• Age younger than five years (peak incidence between six and 15 months)
• Attending group child care
• Bottle feeding while lying down (bottle propping)
• Pacifier use after six months of age
• Family history of ear infections

Environmental and Other Factors

• Exposure to tobacco smoke or air pollution
• Cold-weather seasons when respiratory infections are common
• Lack of breastfeeding in infancy
• Cleft palate or other craniofacial differences

Outer ear infections (otitis externa, or swimmer's ear) have a different cause: water, moisture, or minor injury to the ear canal that allows bacteria or fungi to grow in the canal skin.

Ear infection symptoms often come on quickly. The main symptom is ear pain, but young children who cannot describe pain may show it through behavior.

Common symptoms in children include:

• Tugging, rubbing, or holding the ear
• Fussiness, crying more than usual, and trouble sleeping
• Fever
• Trouble hearing or responding to quiet sounds
• Loss of balance
• Fluid or pus draining from the ear (otorrhea)
• Reduced appetite; sometimes vomiting or lethargy

Common symptoms in adults include:

• Ear pain or a feeling of pressure
• Reduced or muffled hearing
• Fluid drainage from the ear

How Long Do Ear Infection Symptoms Last?

Many ear infections start to improve within 2-3 days, and most resolve within about a week with or without antibiotics.

• Mild middle ear infection: often improves in 48-72 hours (watchful waiting is reasonable in many cases)
• Fluid behind the eardrum (effusion): can linger for weeks to a few months after symptoms clear
• Ear pain and fever: may persist for 48-72 hours even after starting antibiotics
• Seek care sooner if pain is severe, fever is high, or symptoms worsen or do not improve after 2-3 days

Doctors diagnose ear infections based on symptoms and by examining the eardrum. There is no single blood test; the diagnosis is clinical.

A healthcare provider may ask:

• When did the ear pain or other symptoms start?
• Has there been a recent cold, flu, or allergy flare?
• Is there any drainage from the ear?
• Has your child had ear infections before?
• Is there fever, and how high?

Examination and tests may include:

• Otoscopy - looking at the eardrum with a lighted scope for redness, bulging, or fluid
• Pneumatic otoscopy - puffing air against the eardrum to see if it moves; reduced movement suggests fluid behind it
• Tympanometry - measuring eardrum movement to detect middle ear fluid
• Tympanocentesis - rarely, drawing a fluid sample to identify bacteria in difficult or recurrent cases

A middle ear infection is generally diagnosed when the eardrum is bulging or there is new drainage, along with signs of middle ear fluid. Otitis media with effusion (fluid without active infection) is distinguished from acute infection because the eardrum is not bulging.

Treatment depends on the type of infection, the person's age, symptom severity, and whether one or both ears are affected. Many middle ear infections improve on their own.

Pain and Fever Relief

Managing pain is a priority. Acetaminophen (Tylenol) or ibuprofen (Advil, Motrin) can relieve ear pain and fever. Warm or cool compresses may add comfort. Topical anesthetic ear drops are sometimes used but should be avoided if the eardrum may be perforated.

Watchful Waiting (Observation)

Because many ear infections resolve without antibiotics, guidelines support observing for 48-72 hours in lower-risk children with mild symptoms, with a plan to start antibiotics if symptoms do not improve. About 81% of children improve without antibiotics compared with 93% with antibiotics, so antibiotics are used selectively.

Antibiotics for Middle Ear Infection

When antibiotics are needed, high-dose amoxicillin is first-line therapy. Amoxicillin-clavulanate (Augmentin) is used if the child took amoxicillin in the previous 30 days, has purulent conjunctivitis, or does not respond to amoxicillin. For people with penicillin allergy, cefdinir or azithromycin may be used. A single injection of ceftriaxone is an option when a child cannot keep oral medicine down. Treatment usually lasts 10 days for younger children or those with severe symptoms, and 5-7 days for older children with milder symptoms.

Treatment for Outer Ear Infection (Otitis Externa)

Swimmer's ear is usually treated with antibiotic ear drops, often a fluoroquinolone such as ciprofloxacin or ofloxacin, sometimes combined with a steroid (for example, ciprofloxacin-dexamethasone). Keeping the ear dry supports healing.

Ear Tubes for Recurrent Infections

Children with frequent infections (three or more in six months, or four or more in a year) may be referred to an ear, nose, and throat specialist for tympanostomy (ear) tubes.

Most ear infections clear up without lasting problems. Complications are uncommon but more likely with untreated, severe, or repeated infections.

Possible complications include:

• Temporary hearing loss from fluid behind the eardrum
• Persistent fluid in the middle ear (otitis media with effusion)
• Eardrum perforation (a tear that usually heals on its own)
• Speech or developmental delays in young children with long-lasting hearing changes
• Recurrent ear infections
• Mastoiditis - infection spreading to the bone behind the ear
• Rarely, spread of infection to nearby structures, including meningitis
• Cholesteatoma - an abnormal skin growth from chronic infection

Seek prompt medical care for swelling, redness, or pain behind the ear, a stiff neck, severe headache, or new weakness of the face, which can signal a more serious infection.

Not every ear infection can be prevented, but several steps lower the risk, especially in children.

Practical prevention tips:

• Stay up to date on vaccines, including the pneumococcal conjugate vaccine and the annual flu vaccine, which target common causes of ear infections
• Wash hands often and limit exposure to colds and secondhand smoke
• Breastfeed infants when possible; exclusive breastfeeding for at least six months lowers risk
• Feed babies in an upright position and avoid bottle propping
• Reduce pacifier use after six months of age
• Manage allergies that cause nasal and eustachian tube congestion

To help prevent swimmer's ear (otitis externa):

• Dry ears thoroughly after swimming or bathing
• Avoid inserting cotton swabs or objects into the ear canal
• Consider swim earplugs if you are prone to outer ear infections

Mild ear infections often improve on their own, but some situations need medical evaluation.

See a healthcare provider if:

• Ear pain is severe or lasts more than 2-3 days
• Symptoms do not improve or worsen after 48-72 hours
• There is fluid, pus, or blood draining from the ear
• A child younger than six months has any signs of ear infection
• Fever is high (for example, 102.2 degrees F / 39 degrees C or higher)
• Ear infections keep coming back

Seek urgent care for warning signs of a serious infection:

• Swelling, redness, or pain behind the ear
• Severe headache, stiff neck, or confusion
• New facial weakness or trouble with balance
• High fever with a very ill-appearing child

In adults, ear infections are less common, so recurrent infections or persistent fluid should be evaluated to rule out other causes.

Over-the-counter (OTC) medicines can manage ear infection symptoms, but antibiotics that treat the infection itself require a prescription.

OTC options for symptom relief:

• Acetaminophen (Tylenol) - relieves ear pain and reduces fever
• Ibuprofen (Advil, Motrin) - relieves pain and fever (not for infants under six months without medical advice)
• Some OTC drying ear drops may help prevent swimmer's ear but should not be used if the eardrum may be perforated

Prescription required for:

• Oral antibiotics - amoxicillin, amoxicillin-clavulanate (Augmentin), cefdinir, azithromycin
• Antibiotic ear drops - ciprofloxacin, ofloxacin, or ciprofloxacin-dexamethasone for otitis externa
• Injectable antibiotics such as ceftriaxone in select cases

Do not use leftover antibiotics or someone else's prescription. A provider should confirm the type of ear infection before antibiotics are started, since many cases do not need them and unnecessary antibiotics contribute to resistance.