What is the treatment for sinusitis?

Treatment of Sinusitis

For acute bacterial sinusitis, start with amoxicillin or amoxicillin-clavulanate as first-line therapy for 10-14 days, reserving high-dose amoxicillin-clavulanate for patients with severe disease, recent antibiotic exposure, or those in regions with high bacterial resistance. 1, 2

Acute Bacterial Sinusitis

First-Line Antibiotic Selection

• Amoxicillin is the preferred initial agent for uncomplicated acute bacterial sinusitis in both adults and children, given its effectiveness, low cost, and favorable tolerability profile 2
• Amoxicillin-clavulanate (500-875 mg twice daily for adults; 22.5-45 mg/kg twice daily for children based on amoxicillin component) is recommended as an alternative first-line option, particularly when beta-lactamase-producing organisms are suspected 1
• Recent high-quality evidence shows that high-dose amoxicillin-clavulanate does not provide superior clinical outcomes compared to standard-dose formulations in adults with clinically diagnosed acute sinusitis, though it may increase the risk of severe diarrhea 3, 4

Treatment Duration and Response Assessment

• Standard treatment duration is 10-14 days for most antibiotics, continuing until the patient is symptom-free for 7 days 1, 2
• Evaluate clinical response after 3-5 days of initial therapy 1, 2
• If symptoms are improving, complete the full 10-14 day course 2
• If no improvement occurs after 3-5 days, switch to a different antibiotic class 2

Severity-Based Treatment Algorithm

For mild acute bacterial sinusitis:

• Start with amoxicillin or standard-dose amoxicillin-clavulanate 1
• Reassess at 3-5 days 1

For moderate to severe sinusitis or recent antibiotic use:

• Begin with high-dose amoxicillin-clavulanate or a respiratory fluoroquinolone 1

For penicillin-allergic patients:

• Second-generation cephalosporins (cefuroxime axetil) or third-generation cephalosporins (cefpodoxime proxetil, cefdinir) are appropriate alternatives 1, 5
• Macrolides (azithromycin) may be used in non-severe cases and areas with low resistance 5, 6
• Respiratory fluoroquinolones (levofloxacin 500 mg daily for 10-14 days OR 750 mg daily for 5 days) are reserved for treatment failures or complicated cases 1, 7

Second-Line Options for Treatment Failure

• If symptoms persist after initial therapy, switch to high-dose amoxicillin-clavulanate if not already used 2
• Alternative second-line agents include cefuroxime, cefpodoxime, cefprozil, or cefdinir 2
• For protracted cases (21-28 days without improvement), consider broader-spectrum antibiotics with anaerobic coverage (clindamycin or metronidazole in combination) 1, 2

Chronic Sinusitis

Initial Treatment Approach

• Amoxicillin-clavulanate is first-line therapy for chronic ethmoid sinusitis due to effectiveness against common pathogens including resistant bacteria 5
• Treatment duration is typically 10-14 days initially, with continuation for another 10-14 days if partial response occurs 5
• For penicillin-allergic patients, use cephalosporins (cefuroxime, cefpodoxime, cefprozil, cefdinir) for 10-14 days 5

Essential Adjunctive Therapies

Intranasal corticosteroids:

• Recommended as adjunct to antibiotics for both acute and chronic sinusitis, particularly with marked mucosal edema 1, 5
• Continue daily throughout treatment course 5

Saline irrigation:

• Perform 2-3 times daily to improve mucociliary clearance and reduce nasal congestion 5
• Continue throughout treatment and beyond 5

Oral decongestants:

• May be used short-term (maximum 5 days) to decrease nasal resistance and improve ostial patency 5, 2
• Critical pitfall: Prolonged use beyond 5 days leads to rhinitis medicamentosa (rebound congestion) 5

Special Considerations and Red Flags

High-Risk Anatomic Locations

• Frontal, ethmoidal, or sphenoidal sinusitis requires more aggressive treatment due to higher complication risk 1
• Consider earlier specialist referral and imaging for these locations 1

Complications Requiring Immediate Hospitalization

• Orbital involvement (periorbital edema, vision changes, ophthalmoplegia) 1
• Neurological symptoms (severe headache, altered mental status, meningeal signs) 1
• These require immediate hospitalization and parenteral antibiotics 1

Underlying Conditions to Evaluate

• Assess for allergic rhinitis, immunodeficiency, or anatomical abnormalities in patients with chronic or recurrent sinusitis 1, 5
• Consider referral to allergist-immunologist or otolaryngologist if medical therapy fails 5
• Surgical intervention may be necessary for medically resistant cases 5

Common Pitfalls to Avoid

• Overdiagnosis: Only prescribe antibiotics when symptoms last ≥10-14 days OR severe symptoms (fever, purulent discharge, facial pain) are present for 3-4 consecutive days 2
• Inadequate duration: Patients must complete the full 10-14 day course even if symptoms improve earlier to prevent relapse 2
• Wrong spectrum: Inadequate antibiotic spectrum for chronic sinusitis leads to treatment failure 5
• Ignoring underlying causes: Failure to address allergic rhinitis or other risk factors perpetuates the problem 5
• Decongestant overuse: Limit topical/oral decongestants to 5 days maximum 5
• Delayed referral: Refer to specialist if symptoms persist beyond 21-28 days of appropriate antibiotic therapy with CT imaging 1