Acute Otitis Media in Childhood
Clinical Snapshot
Acute otitis media (AOM) is an infection of the middle ear, defined by the presence of middle ear effusion together with signs of middle ear inflammation — a red, bulging, immobile tympanic membrane.[1] It is usually preceded by a viral upper respiratory tract infection that impairs eustachian tube function, allowing nasopharyngeal bacteria to invade the middle ear; bacteria are isolated in most cases, but viral co-infection is common. Management is age- and risk-stratified, not one-size-fits-all: children under 6 months and those who are toxic-appearing, highly febrile, or in severe pain need an antibiotic started immediately, while well-appearing children over 6 months with mild, uncomplicated illness and reliable follow-up can be offered watchful waiting for 48 hours first — roughly 60% of AOM resolves spontaneously within that window regardless of antibiotics.[2]
Recognize the Condition
Typical presentation
An irritable child with 2-3 days of fever, runny nose, and cough — the presentation of a viral URTI — who then develops otalgia. Ear pain is not always easily communicated by infants and toddlers; disturbed sleep, irritability, tugging at the ear, or rubbing the head may be the only clue.
Etiology
Both viral and bacterial pathogens are involved; the primary bacterial pathogens are Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. Untreated, spontaneous resolution rates differ substantially by pathogen — roughly 20% for S. pneumoniae, 50% for H. influenzae, and 75% for M. catarrhalis — which is part of why a watchful-waiting approach is reasonable for many children. Since pneumococcal conjugate vaccination became routine, the proportion of AOM caused by S. pneumoniae has fallen while H. influenzae has become relatively more common, and penicillin-resistant S. pneumoniae has become substantially less common (well under 1% of invasive isolates in a large Western Canadian surveillance program).
Resistance mechanisms — why the drug choice depends on them
S. pneumoniae penicillin resistance
Caused by altered penicillin-binding proteins, reducing drug affinity — doubling the amoxicillin dose overcomes this by raising the middle-ear drug concentration high enough to kill resistant strains.
H. influenzae and M. catarrhalis resistance
Caused by beta-lactamase production — adding clavulanate (a beta-lactamase inhibitor) restores amoxicillin's activity against these organisms.
This is why the two escalation questions in AOM are genuinely different: "does this child need more amoxicillin?" (double the dose) versus "does this child need a different drug?" (add clavulanate) — and why understanding which pathogen is more likely changes the choice.
Risk Factors
Risk factors for infection
- Recent viral upper respiratory tract infection.
- Exposure to tobacco smoke — a modifiable risk factor for AOM itself.
- Daycare attendance.
- Lack of breastfeeding — breastfeeding is protective against nasopharyngeal colonization and lowers AOM rates.
- Craniofacial anomalies, immunodeficiency, or Down syndrome.
Risk factors for drug-resistant organisms — changes the initial antibiotic choice
- Recent antibiotic use (within the prior 3 months).
- Daycare attendance.
- Recent episode of AOM.
- Prior treatment failure or early recurrence.
A child with any of these should start on high-dose therapy rather than standard-dose, rather than being escalated only after a first agent fails.
Red Flags & Refer
Refer/escalate immediately for any of the following:
- Age under 6 weeks with suspected AOM — refer to the nearest emergency department for full assessment; bacteremia risk from gram-negative organisms, since fever in this age group may reflect sepsis rather than isolated AOM.
- Signs of mastoiditis — postauricular swelling, erythema, tenderness, or a protruding auricle.
- Facial nerve palsy.
- Meningitis or labyrinthitis.
- Toxic appearance.
- Significant swelling, erythema, or tenderness of the external auditory canal with debris or discharge — suggests otitis externa instead and needs a different management approach.
- Refer to ENT for multiple treatment failures unresponsive to therapy, for culture-directed therapy.
- Refer to ENT for recurrent AOM (≥3 episodes in 6 months or ≥4 in 12 months), for consideration of myringotomy and tympanostomy tubes, plus an audiology assessment to check for conductive hearing loss.
Assessment & Diagnosis
Diagnosis requires both of the following
AOM diagnosis needs evidence of both middle ear effusion and middle ear inflammation — neither alone is sufficient.
The four-feature tympanic membrane exam
| Feature | Finding suggesting AOM |
|---|---|
| Colour | Red (erythematous) |
| Position | Displaced or bulging |
| Translucency | Opaque (loss of the normal light reflex/landmarks) |
| Mobility | Immobile on pneumatic otoscopy |
Proper visual inspection may require the child to be restrained by a parent, good lighting, and removal of any cerumen obscuring the view — do not diagnose AOM from an inadequate exam.
History
- Fever, and nonspecific viral URTI symptoms (cough, coryza) that often precede the ear symptoms.
- Otalgia — often the best clue, but ask about disturbed sleep, irritability, ear tugging, or head rubbing in infants and toddlers who cannot verbalize pain.
- Toxic appearance, temperature ≥39°C, or severe otalgia — these define "severe illness" and change the treatment pathway (see Clinical Decision Algorithm).
- Any episode of AOM in the preceding month, prior mastoiditis, intracranial infection, or facial paralysis — a prior complicated course rules out watchful waiting for this episode.
- Craniofacial anomalies, immunodeficiency, cardiac or pulmonary disease, or Down syndrome — these also rule out watchful waiting.
- Whether parents/caregivers can reliably recognize worsening illness and access medical care if watchful waiting is chosen.
Examination
- Head and neck exam to rule out other referred causes of ear pain — mastoiditis, dental abscess.
- The four-feature tympanic membrane exam above.
- Assess the external auditory canal — significant swelling, erythema, tenderness, or discharge suggests otitis externa instead of, or in addition to, AOM.
Treatment Targets
- Relieve symptoms — fever, irritability, pain.
- Sterilize the middle ear.
- Prevent complications — mastoiditis, intracranial infection, facial paralysis.
- Avoid inappropriate antibiotic therapy, which drives resistant pathogens and adverse effects such as antibiotic-associated diarrhea.
Choose Initial Treatment
1st line in a child over 6 months with mild, uncomplicated illness (fever <39°C, mild otalgia, no prior AOM in the last month, no craniofacial anomaly/immunodeficiency/cardiopulmonary disease/Down syndrome/prior complicated AOM, and reliable caregiver follow-up), offer watchful waiting for 48 hours with adequate analgesia and a clear plan to start antibiotics if the child worsens or does not improve.[2]
Do not offer watchful waiting to a child under 6 months, a toxic-appearing or highly febrile (≥39°C) or severely painful child, or one who has already been significantly ill for 48 hours — start an antibiotic immediately in those children.
1st-line antibiotic is amoxicillin — standard-dose for a child with no risk factors for drug-resistant organisms, high-dose for a child with any risk factor for resistance (recent antibiotic use, daycare, recent AOM episode, or prior treatment failure/early recurrence).
2nd line / treatment failure is high-dose amoxicillin/clavulanate if symptoms have not improved after 72 hours of amoxicillin.
Non-Pharmacologic Treatment
- Adequate analgesia is essential in the early stages of infection, whether or not an antibiotic is given.
- Watchful waiting, for children who meet the criteria above — provide caregivers with a clear rationale, a safety-net plan for worsening symptoms, and either a delayed/backup antibiotic prescription or a concrete follow-up plan.
- Nasal and oral decongestants, alone or combined with an antihistamine, have not shown benefit in resolving symptoms, infection, or preventing complications — they are not recommended.
- Probiotics can reduce the risk of antibiotic-associated diarrhea when an antibiotic is used (number needed to treat = 9).
- Vaccination — influenza and pneumococcal conjugate vaccines reduce AOM incidence; encourage up-to-date immunization per the current Canadian Immunization Guide, especially in children with recurrent AOM.
Special Populations
Under 6 weeks of age
Refer to the nearest emergency department for full assessment — investigate for bacteremia, since fever in this age group may reflect sepsis rather than isolated AOM.
6 weeks to 6 months
Treat all cases with an antibiotic (no watchful waiting) for 10 days — standard-dose or high-dose amoxicillin as first choice.
Recurrent AOM (≥3 episodes in 6 months or ≥4 in 12 months)
Refer to ENT for consideration of myringotomy and tympanostomy tubes, and for an audiology assessment. Consider conjugate pneumococcal vaccine if under 5 years of age if not already received, and give influenza vaccine yearly at any age.
Penicillin allergy
Verify a true anaphylactic-type allergy — hives; swelling of lips, mouth, or throat; wheezing; hypotension; sudden-onset vomiting and diarrhea — versus a nonspecific reaction such as a rash or GI upset, which parents and patients commonly overestimate as an allergy. Consider penicillin skin testing when the history is unclear. A dissimilar-side-chain cephalosporin (cefuroxime) is an acceptable option even after a prior penicillin allergy, including some IgE-mediated reactions; reserve macrolides/clindamycin for confirmed type I hypersensitivity.
Monitoring & Follow-Up
Most children have middle ear effusion for some time after completing therapy — there is no need to treat an abnormal-appearing tympanic membrane in an asymptomatic child. If middle ear effusion persists beyond 3 months, arrange an audiology assessment to evaluate hearing. Treatment failure is defined as no improvement after 72 hours of antibiotic therapy.
Common Errors to Avoid
- Diagnosing AOM from effusion alone, or inflammation alone — both are required.
- Prescribing decongestants or antihistamines for AOM symptoms — no proven benefit.[3]
- Treating an asymptomatic child's abnormal-appearing tympanic membrane found incidentally after therapy.
- Labelling a nonspecific reaction (rash, GI upset) as a penicillin "allergy" without clarifying whether it was truly anaphylactic/IgE-mediated — this unnecessarily pushes children toward less effective, broader-spectrum alternatives.
- Using high-dose amoxicillin/clavulanate as a single combined-ratio prescription at high dose — this increases diarrhea risk; give as 2 simultaneous prescriptions instead (see Drug Tables).
- Offering watchful waiting to a child under 6 months, or one who is toxic-appearing, highly febrile, or has a craniofacial anomaly, immunodeficiency, cardiopulmonary disease, or Down syndrome.
- Reaching for azithromycin or clarithromycin as a routine alternative rather than reserving macrolides for true type I beta-lactam hypersensitivity — resistance and failure rates are rising.
Clinical Decision Algorithm
Drug Tables
How to use this table: Doses are adult doses and require patient-specific confirmation (renal/hepatic function, weight, allergy history). Pediatric dosing is weight-based per the current product monograph unless stated. Drug pricing is intentionally omitted. Select any drug name to open its complete Pharmasist Drug Database page.
Penicillins
| Drug | Dosage | Adverse effects | Comments |
|---|---|---|---|
| Amoxicillin (standard-dose) | Dose: 40-50 mg/kg/day PO divided TID Maximum: 4 g/day | Excellent safety profile. Occasionally causes mild diarrhea. Maculopapular rash occurs uncommonly but is difficult to distinguish from a concomitant viral exanthem. | Drug of choice. Reserve standard-dose for the limited number of children at low risk of drug-resistant bacteria (no daycare, no antibiotic in the prior 3 months). Most children tolerate the taste of the suspension. |
| Amoxicillin (high-dose) | Dose: 75-90 mg/kg/day PO divided BID Maximum: 4 g/day | Excellent safety profile. Occasionally causes mild diarrhea. Maculopapular rash occurs uncommonly. | For pneumococci with decreased susceptibility to penicillins/cephalosporins, amoxicillin is more active than cephalosporins. |
| Amoxicillin/clavulanate (high-dose) | Dose: 75-90 mg/kg/day (amoxicillin component) PO divided BID-TID Maximum: 4 g/day (amoxicillin component) | Excellent safety profile. Diarrhea occurs frequently. Maculopapular rash occurs uncommonly. | Use after failure of high-dose amoxicillin. Avoid the original low-dose formulations (Clavulin-125F, Clavulin-250F) in the high-dose protocol — the higher clavulanate content increases diarrhea. To reduce diarrhea risk, give as 2 simultaneous prescriptions: amoxicillin 40 mg/kg/day PLUS a 7:1-formulation amoxicillin/clavulanate liquid (Clavulin-200 or Clavulin-400) dosed at 40 mg/kg/day of the amoxicillin component. Alternatively, one 7:1 formulation alone at 80 mg/kg/day of the amoxicillin component may be used but tends to cause more diarrhea — dividing TID rather than BID may improve tolerance. When prescribing, write "high-dose amoxicillin intended" on the prescription to avoid dispensing confusion. Most children tolerate the taste of the suspension. |
Cephalosporins
| Drug | Dosage | Adverse effects | Comments |
|---|---|---|---|
| Cefprozil | Dose: 30 mg/kg/day PO divided BID Maximum: 1 g/day | Low incidence of diarrhea or GI upset. | Most children tolerate the taste of the liquid formulation, which is well absorbed. |
| Cefuroxime axetil | Dose: 30 mg/kg/day PO divided BID-TID Maximum: 1 g/day | Low incidence of diarrhea or GI upset. | An acceptable treatment option in penicillin allergy, including some IgE-mediated reactions, because of its dissimilar side chain. Suspension and tablets have an unpleasant, bitter taste. |
| Ceftriaxone | Dose: 50 mg/kg (maximum 1 g) IM/IV once daily x 3 days | Pain at the injection site when given IM. | Second- or third-line agent — most effective cephalosporin against AOM pathogens but reserved given the injectable route. May be diluted with plain 1% lidocaine to a final concentration of 300 mg/mL to reduce IM injection pain. Do not reconstitute or mix with calcium-containing solutions. |
Lincosamides
| Drug | Dosage | Adverse effects | Comments |
|---|---|---|---|
| Clindamycin | Standard dose: 30 mg/kg/day PO/IV divided TID, maximum 1.8 g/day Severe infection (IV): Up to 40 mg/kg/day divided TID-QID, maximum 2.7 g/day | Nausea, vomiting, diarrhea (common); esophagitis, rash, C. difficile-associated diarrhea. | Reserve for true anaphylactic-type beta-lactam allergy and/or treatment failure. Does not cover H. influenzae or M. catarrhalis. Suspension has an unpleasant taste; capsules at a 150 mg-multiple dose can be opened and mixed with a soft solid (apple sauce, pudding, chocolate sauce) if swallowing capsules is not feasible. |
Macrolides
Reserve for true type I (anaphylactic-type) beta-lactam hypersensitivity — rising resistance and treatment-failure rates versus amoxicillin.
| Drug | Dosage | Adverse effects | Comments |
|---|---|---|---|
| Azithromycin | 5-day course, Day 1: 10 mg/kg (maximum 500 mg) PO once daily 5-day course, Days 2-5: 5 mg/kg (maximum 250 mg) PO once daily 3-day course (alternative): 10 mg/kg (maximum 500 mg) PO once daily | Low incidence of diarrhea or GI upset. | Pneumococci with decreased penicillin/cephalosporin susceptibility are sometimes also azithromycin-resistant. A short course may improve adherence. Most children tolerate the taste of the suspension. |
| Clarithromycin | Dose: 15 mg/kg/day PO divided BID Maximum: 1000 mg/day | Diarrhea or vomiting (15%). | Pneumococci with decreased penicillin/cephalosporin susceptibility are sometimes also clarithromycin-resistant. Because of a bitter aftertaste, give the suspension with food and/or juice. |
Fluoroquinolones
Not a routine option — for treatment failure in a penicillin-allergic child, only after infectious disease consultation.
| Drug | Dosage | Adverse effects | Comments |
|---|---|---|---|
| Levofloxacin | Use: Per infectious disease specialist consultation — no standard pediatric AOM regimen established | GI upset, headache; rare tendinopathy, peripheral neuropathy, CNS effects. | Reserve for treatment failure in a true beta-lactam-allergic child, and only after consultation with an infectious disease specialist, given the class safety profile in children. |
References
- The diagnosis and management of acute otitis media — Pediatrics, American Academy of Pediatrics (Lieberthal AS, Carroll AE, Chonmaitree T, et al.). Pediatrics 2013;131(3):e964-e999
- Antibiotics for acute otitis media in children — Cochrane Database of Systematic Reviews (Venekamp RP, Sanders SL, Glasziou PP, et al.). Cochrane Database Syst Rev 2015;(6):CD000219
- Decongestants and antihistamines for acute otitis media in children — Cochrane Database of Systematic Reviews (Coleman C, Moore M). Cochrane Database Syst Rev 2008;(3):CD001727
- Management of acute otitis media in children six months of age and older — Canadian Paediatric Society, Infectious Diseases and Immunization Committee (Le Saux N, Robinson JL). Paediatr Child Health 2016;21(1):39-50
- Shortened antimicrobial treatment for acute otitis media in young children — New England Journal of Medicine (Hoberman A, Paradise JL, Rockette HE, et al.). N Engl J Med 2016;375(25):2446-2456
- Antibiotics for acute otitis media: a meta-analysis with individual patient data — The Lancet (Rovers MM, Glasziou P, Appelman CL, et al.). Lancet 2006;368(9545):1429-1435
Professional reference only. Apply clinical judgment and verify patient-specific decisions against current authoritative guidance and product information.