Treatment of Pediatric Sinusitis
For children with acute bacterial sinusitis, amoxicillin 45 mg/kg/day divided twice daily for 10-14 days is the first-line treatment, but antibiotics should only be initiated for persistent symptoms ≥10 days without improvement, severe presentation (fever ≥39°C for ≥3 consecutive days with thick nasal discharge), or worsening symptoms after initial improvement. 1
Distinguishing Bacterial Sinusitis from Viral Upper Respiratory Infection
Before initiating antibiotics, confirm the diagnosis using one of three clinical patterns 2, 1:
- Persistent pattern (most common): Nasal discharge or daytime cough lasting ≥10 days without improvement 2
- Severe pattern: Fever ≥39°C (102.2°F) for ≥3 consecutive days with thick, colored nasal discharge 2, 1
- Worsening pattern: Initial improvement from a viral cold followed by new-onset fever ≥38°C (100.4°F) or substantial increase in symptoms within 10 days 2
Critical pitfall: Thick, colored mucus alone does not indicate bacterial sinusitis—fewer than 1 in 15 children develop true bacterial infection during or after a common cold 2. Most viral colds produce cloudy or colored mucus that clears by day 10 without antibiotics 2.
First-Line Antibiotic Therapy
Amoxicillin is the preferred first-line agent due to effectiveness against Streptococcus pneumoniae, favorable safety profile, and low cost 1:
- Standard dosing: 45 mg/kg/day divided twice daily (up to 1.5-4 g/day) for 10-14 days 1
- High-risk dosing: 90 mg/kg/day of amoxicillin-clavulanate for children with recent antibiotic exposure, daycare attendance, or age <2 years 1
Alternative for penicillin allergy (type 1 or non-type 1 hypersensitivity): Cefdinir, cefuroxime, or cefpodoxime 2
Avoid trimethoprim/sulfamethoxazole and azithromycin due to high resistance rates of S. pneumoniae and H. influenzae 2. The FDA label confirms azithromycin dosing at 10 mg/kg once daily for 3 days for acute bacterial sinusitis 3, but resistance surveillance makes this a poor choice 2.
Watchful Waiting vs. Immediate Antibiotics
For children with persistent pattern only (mild symptoms ≥10 days), either approach is acceptable 2, 1:
- Observation option: Allow up to 3 additional days for spontaneous improvement before starting antibiotics 2
- Immediate antibiotics: Reasonable if symptoms significantly impair quality of life 2
For severe or worsening patterns, immediate antibiotic treatment is mandatory to achieve faster recovery and prevent complications 2, 1.
Treatment Failure and Reassessment
Reassess at 72 hours after initiating antibiotics 2, 1:
- If worsening or no improvement: Switch to high-dose amoxicillin-clavulanate (90 mg/kg/day of amoxicillin component) 1
- Second-line alternatives include cephalosporins or intramuscular ceftriaxone 1
Treatment duration: Continue for 10-14 days total, or alternatively treat for 7 days after symptoms resolve (ensuring minimum 10 days total) 2.
Adjunctive Therapies
Recommended adjuncts to improve symptoms and quality of life 1:
- Saline nasal irrigation: Improves nasal airflow, quality of life, and total symptom scores compared to placebo 4
- Analgesics/antipyretics: For pain and fever management 1
- Intranasal corticosteroids: May provide symptomatic relief 1
Avoid these interventions due to insufficient evidence or potential harm 2, 1:
- Oral or topical decongestants
- Antihistamines (unless concurrent allergic rhinitis)
- Mucolytics
The Cochrane review found no appropriately designed studies supporting decongestants, antihistamines, or nasal irrigation as primary treatments 2, though saline irrigation has shown benefit as adjunctive therapy 4.
Post-Viral Rhinosinusitis: When NOT to Use Antibiotics
Important distinction: For post-viral acute rhinosinusitis (symptoms 5-10 days without meeting bacterial criteria), antibiotics provide no benefit 2. Three randomized controlled trials in children showed no difference in cure rates at 14 days between antibiotics and placebo 2. The European Position Paper advises against antibiotics for this population due to lack of efficacy and increased adverse events 2.
Red Flags Requiring Urgent Evaluation
Suspect complications and consider hospitalization with parenteral antibiotics if 2, 1:
- Periorbital or orbital swelling/cellulitis, proptosis, or impaired extraocular movements (orbital complications)
- Severe headache, photophobia, seizures, altered mental status, or focal neurologic signs (intracranial complications including meningitis, brain abscess, subdural/epidural empyema)
- High fever unresponsive to antipyretics
- Visual changes
Imaging for complications only: Contrast-enhanced CT or MRI should be performed when orbital or CNS complications are suspected, but not for routine diagnosis of uncomplicated sinusitis 2.
Age-Specific Considerations
Children <6 months: Safety and effectiveness of antibiotic treatment for acute bacterial sinusitis not established 3
Children 6 months to 18 years: Standard treatment protocols apply as outlined above 2, 1
Recurrent acute bacterial sinusitis (≥4 episodes per year with symptom-free intervals): Evaluate for underlying conditions including allergic rhinitis, immunodeficiency, cystic fibrosis, or anatomical abnormalities 2. Avoid prolonged prophylactic antibiotics due to resistance concerns 2.