What is the recommended treatment for sinus infections?

Treatment of Acute Bacterial Sinusitis

For uncomplicated acute maxillary sinusitis in adults, start with amoxicillin 500 mg twice daily (or 875 mg twice daily for severe infections) for 10-14 days, reserving amoxicillin-clavulanate and fluoroquinolones for treatment failures or complicated cases. 1

First-Line Antibiotic Selection

Standard Maxillary Sinusitis

• Amoxicillin is the preferred first-line agent at 500 mg twice daily for most patients, or 875 mg twice daily for more severe infections 1
• Treatment duration should be 10-14 days until symptom-free for 7 days 1
• Amoxicillin-clavulanate (500-875 mg twice daily) is reserved as second-line therapy for patients who fail initial treatment or have risk factors for resistant bacteria 1
• Alternative first-line options include second-generation cephalosporins (cefuroxime-axetil) or third-generation cephalosporins (cefpodoxime-proxetil, cefdinir) 2, 1

Penicillin-Allergic Patients

• Use cephalosporins: cefuroxime-axetil, cefpodoxime-proxetil, or cefdinir 1
• Pristinamycin is an alternative for true beta-lactam allergy 2
• Do NOT use azithromycin or other macrolides due to high resistance rates in S. pneumoniae and H. influenzae 1

Treatment Based on Anatomic Location

High-Risk Sinusitis Sites (Frontal, Ethmoidal, Sphenoidal)

• These locations require more aggressive initial therapy due to risk of serious complications (meningitis, orbital complications, cavernous sinus thrombosis) 2
• Start with fluoroquinolones active against pneumococci: levofloxacin or moxifloxacin 2, 1
• These patients may require hospitalization if clinical signs suggest complications (meningeal syndrome, exophthalmos, palpebral edema, ocular mobility disorders, severe pain preventing sleep) 2

Adjunctive Therapies

Intranasal Corticosteroids

• Recommended as adjunct to antibiotics in both acute and chronic sinusitis to decrease mucosal inflammation 2, 1
• Continue for 3 months if cough or symptoms resolve with initial therapy 2

Oral Corticosteroids

• Consider short-term use (e.g., dexamethasone 4 mg) for acute hyperalgic sinusitis (severe pain) or marked mucosal edema 1
• Never use as monotherapy—antibiotics remain essential for bacterial infection 1

Decongestants

• Topical decongestants (oxymetazoline) may provide symptomatic relief but limit use to 3-5 days maximum to avoid rebound congestion 2, 3
• Evidence for oral or topical decongestants is limited, though they may help symptomatically 2

Treatment Failure Protocol

If No Improvement After 3-5 Days

• Switch to amoxicillin-clavulanate (875 mg twice daily) for better coverage against beta-lactamase-producing organisms 1
• Consider fluoroquinolones (levofloxacin, moxifloxacin) as second-line agents 1
• Obtain imaging (CT) and consider bacteriological testing before escalating therapy 2

For Partial Response

• Continue current antibiotic for another 10-14 days 1
• Reassess for underlying factors: allergic rhinitis, immunodeficiency, anatomic abnormalities 1, 3

Pediatric Considerations

Dosing for Children

• Amoxicillin 45 mg/kg/day in 2 divided doses for standard therapy 1
• High-dose amoxicillin 80-90 mg/kg/day in 2 divided doses for areas with high S. pneumoniae resistance or risk factors (age <2 years, daycare attendance, recent antibiotic use) 1
• Amoxicillin-clavulanate 80-90 mg/kg/day of amoxicillin component with 6.4 mg/kg/day clavulanate in 2 divided doses for children with risk factors 1
• For penicillin-allergic children: cefpodoxime proxetil 8 mg/kg/day in two doses 1

Critical Pitfalls to Avoid

Antibiotic Selection Errors

• Never use azithromycin for acute bacterial sinusitis—resistance rates are too high despite FDA approval for 3-day dosing 1, 4
• Do not use fluoroquinolones as routine first-line therapy; reserve them to prevent resistance development 1
• Avoid cefixime—it is specifically excluded from recommended cephalosporins 2

Duration Errors

• Do not stop antibiotics when symptoms improve—complete the full 10-14 day course to prevent relapse 1
• Some cephalosporins (cefuroxime-axetil, cefpodoxime-proxetil) are effective in 5-day courses, but this is not standard for all agents 2

Diagnostic Errors

• Do not treat viral upper respiratory infections with antibiotics—wait at least 7-10 days to distinguish bacterial from viral sinusitis 2, 5
• Unilateral purulent rhinorrhea with facial pain worsening when bending forward suggests bacterial maxillary sinusitis requiring antibiotics 2
• Bilateral, diffuse nasal symptoms in an epidemic context likely represent viral infection and do not require immediate antibiotics 2

When to Refer to Specialist

• Sinusitis refractory to usual antibiotic treatment after two courses 1
• Recurrent sinusitis (≥3 episodes per year) requiring evaluation for allergic rhinitis, immunodeficiency, or anatomic abnormalities 1, 3
• Suspected complications requiring hospitalization and parenteral antibiotics 2
• Need for endoscopic sinus surgery in chronic cases with documented anatomic obstruction 2