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Otitis Media (Acute)


Richard T. Miyamoto

, MD, MS, Indiana University School of Medicine

Last full review/revision Jun 2020| Content last modified Jun 2020
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Acute otitis media is a bacterial or viral infection of the middle ear, usually accompanying an upper respiratory infection. Symptoms include otalgia, often with systemic symptoms (eg, fever, nausea, vomiting, diarrhea), especially in the very young. Diagnosis is based on otoscopy. Treatment is with analgesics and sometimes antibiotics.

Although acute otitis media can occur at any age, it is most common between ages 3 months and 3 years. At this age, the eustachian tube is structurally and functionally immature—the angle of the eustachian tube is more horizontal, and the angle of the tensor veli palatini muscle and the cartilaginous eustachian tube renders the opening mechanism less efficient.

The etiology of acute otitis media may be viral or bacterial. Viral infections are often complicated by secondary bacterial infection. In neonates, gram-negative enteric bacilli, particularly Escherichia coli, and Staphylococcus aureus cause acute otitis media. In older infants and children < 14 years, the most common organisms are Streptococcus pneumoniae, Moraxella (Branhamella) catarrhalis, and nontypeable Haemophilus influenzae; less common causes are group A beta-hemolytic streptococci and S. aureus. In patients > 14 years, S. pneumoniae, group A beta-hemolytic streptococci, and S. aureus are most common, followed by H. influenzae.

Risk factors

The presence of smoking in the household is a significant risk factor for acute otitis media. Other risk factors include a strong family history of otitis media, bottle feeding (ie, instead of breastfeeding), and attending a day care center.


Complications of acute otitis media are uncommon. In rare cases, bacterial middle ear infection spreads locally, resulting in acute mastoiditis, petrositis, or labyrinthitis. Intracranial spread is extremely rare and usually causes meningitis, but brain abscess, subdural empyema, epidural abscess, lateral sinus thrombosis, or otitic hydrocephalus may occur. Even with antibiotic treatment, intracranial complications are slow to resolve, especially in immunocompromised patients.

Symptoms and Signs of Acute Otitis Media

The usual initial symptom is earache, often with hearing loss. Infants may simply be cranky or have difficulty sleeping. Fever, nausea, vomiting, and diarrhea often occur in young children. Otoscopic examination can show a bulging, erythematous tympanic membrane (TM) with indistinct landmarks and displacement of the light reflex. Air insufflation (pneumatic otoscopy) shows poor mobility of the TM. Spontaneous perforation of the TM causes serosanguineous or purulent otorrhea.

Severe headache, confusion, or focal neurologic signs may occur with intracranial spread of infection. Facial paralysis or vertigo suggests local extension to the fallopian canal or labyrinth.

Diagnosis of Acute Otitis Media

  • Clinical evaluation

Diagnosis of acute otitis media usually is clinical, based on the presence of acute (within 48 hours) onset of pain, bulging of the tympanic membrane and, particularly in children, the presence of signs of middle ear effusion on pneumatic otoscopy. Except for fluid obtained during myringotomy, cultures are not generally done.

Treatment of Acute Otitis Media

  • Analgesics

  • Sometimes antibiotics

  • Rarely myringotomy

Analgesia should be provided when necessary, including to pre-verbal children with behavioral manifestations of pain (eg, tugging or rubbing the ear, excessive crying or fussiness). Oral analgesics, such as acetaminophen or ibuprofen, are usually effective; weight-based doses are used for children. A variety of topical agents are available by prescription and over the counter. Although not well studied, some topical agents may provide transient relief but probably not for more than 20 to 30 minutes. Topical agents should not be used when there is a tympanic membrane perforation.

Although 80% of cases resolve spontaneously, in the US, antibiotics are often given ([1]; see table Antibiotics for Otitis Media). Antibiotics relieve symptoms quicker (although results after 1 to 2 weeks are similar) and may reduce the chance of residual hearing loss and labyrinthine or intracranial sequelae. However, with the recent emergence of resistant organisms, pediatric organizations have strongly recommended initial antibiotics only for certain children (eg, those who are younger or more severely ill—see table Antibiotics in Children With Acute Otitis Media) or for those with recurrent acute otitis media (eg, 4 episodes in 6 months).

Others, provided there is good follow-up, can safely be observed for 48 to 72 hours and given antibiotics only if no improvement is seen; if follow-up by phone is planned, a prescription can be given at the initial visit to save time and expense. Decision to observe should be discussed with the caregiver.


Antibiotics for Otitis Media


Dose* (by Age)


Initial treatment


< 14 years: 40–45 mg/kg every 12 hours

> 14 years: 500 mg every 8 hours

Preferred unless the child has one of the following:

  • Received amoxicillin in the past 30 days

  • Purulent conjunctivitis

  • Recurrent acute otitis media unresponsive to amoxicillin

High-dose regimen for possible resistant organisms



14 mg/kg once a day or 7 mg/kg every 12 hours


< 14 years: 15 mg/kg every 12 hours

> 14 years: 500 mg every 12 hours

Maximum 1000 mg/day


5 mg/kg every 12 hours


50 mg/kg IM or IV once

May repeat at 72 hours

Consider particularly for children with severe vomiting or who will not swallow antibiotic liquids

Resistant cases‡


< 14 years: 40–45 mg/kg every 12 hours

14 years: 500 mg every 12 hours

Preferred; dose based on amoxicillin component

Use new formulation to limit clavulanate to maximum of 10 mg/kg/day


50 mg/kg IM or IV once a day for 3 days

Can use even if failed on oral cephalosporin

Considered if adherence is likely to be poor


10 to 13 mg/kg every 8 hours

2nd-line alternative, consider using along with a cephalosporin

* Treatment duration is typically 10 days for children < 2 years and 7 days for older children unless otherwise specified. Drugs are given orally unless otherwise specified.

† Cross reactivity of 2nd- and 3rd-generation cephalosporins with penicillin is very low.

‡ No improvement after 48 to 72 hours of treatment, or previous resistant infection; amoxicillin used in the previous 30 days; or concurrent purulent conjunctivitis

Data from Lieberthal AS, Carroll AE, Chonmaitree T, et al: The diagnosis and management of acute otitis media. Pediatrics e964–99, 2013.


Guidelines for Using Antibiotics in Children With Acute Otitis Media*



Severe symptoms† (unilateral or bilateral)

Bilateral disease

Unilateral disease, no severe symptoms

< 6 months‡





6 months to 2 years




Antibiotics or observe 48 to 72 hours§

2 years



Antibiotics or observe 48 to 72 hours§

Antibiotics or observe 48 to 72 hours§

* These guidelines apply only to children who meet the diagnostic criteria for acute otitis media (eg, acute [within 48 hours] onset of pain, bulging of the tympanic membrane, and signs of middle ear effusion on pneumatic otoscopy).

† Symptoms include temperature 39° C rectally any time within previous 24 hours or moderate to severe otalgia for > 48 hours, or physician’s judgment that child is seriously ill.

‡ The guidelines in the Pediatrics article from which this table was derived do not include this age group in which observation has not been thoroughly studied. Thus it is reasonable to continue to treat with antibiotics.

§ Decision making should be shared with parents. Observation is appropriate only if phone or office follow-up can be assured within 48 to 72 hours; antibiotics are started if no improvement.

Modified from Lieberthal AS, Carroll AE, Chonmaitree T, et al: The diagnosis and management of acute otitis media. Pediatrics e964–99, 2013.

All patients receive analgesics (eg, acetaminophen, ibuprofen).

In adults, topical intranasal vasoconstrictors, such as phenylephrine 0.25% 3 drops every 3 hours, improve eustachian tube function. To avoid rebound congestion, these preparations should not be used > 4 days. Systemic decongestants (eg, pseudoephedrine 30 to 60 mg orally every 6 hours as needed) may be helpful. Antihistamines (eg, chlorpheniramine 4 mg orally every 4 to 6 hours for 7 to 10 days) may improve eustachian tube function in people with allergies but should be reserved for the truly allergic.

For children, neither vasoconstrictors nor antihistamines are of benefit.

Myringotomy may be done for a bulging tympanic membrane, particularly if severe or persistent pain, fever, vomiting, or diarrhea is present. The patient’s hearing, tympanometry, and tympanic membrane appearance and movement are monitored until normal.

Treatment reference

Prevention of Acute Otitis Media

Routine childhood vaccination against pneumococci (with pneumococcal conjugate vaccine), H. influenzae type B, and influenza decreases the incidence of acute otitis media. Infants should not sleep with a bottle, and elimination of household smoking may decrease incidence. Prophylactic antibiotics are not recommended for children who have recurrent episodes of acute otitis media.

Recurrent acute otitis media and recurrent secretory otitis media may be prevented by the insertion of tympanostomy tubes.

Key Points

  • Give analgesics to all patients.

  • Antibiotics should be used selectively based on the age of the patient, severity of illness, and availability of follow-up.

  • Antihistamines and decongestants are not recommended for children; oral or nasal decongestants may help adults, but antihistamines are reserved for adults with an allergic etiology.

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