What is the treatment for acute sinusitis?

Treatment of Acute Sinusitis

Initial Management: Symptomatic Treatment First

Most cases of acute sinusitis are viral and should be treated with symptomatic management alone—antibiotics are reserved for specific clinical scenarios indicating bacterial infection. 1

First-Line Symptomatic Therapy

• Analgesics (acetaminophen or NSAIDs) should be offered for pain relief in all patients 1
• Saline nasal irrigation promotes mucus clearance and temporarily reduces tissue edema 1
• Topical nasal decongestants may be used short-term (≤3-5 days) to relieve nasal congestion, but prolonged use leads to rebound congestion 1
• Intranasal corticosteroids provide modest but clinically important benefits with a number needed to treat of 14 1

When to Initiate Antibiotics

Antibiotics should only be started when patients meet one of three specific criteria: 1

1. Persistent symptoms lasting more than 10-14 days without improvement 1
2. Severe symptoms at onset (high fever ≥102°F with purulent nasal discharge for 3-4 consecutive days) 1
3. Worsening symptoms after initial improvement (double-worsening pattern) 1

Antibiotic Selection

First-Line Antibiotic Choice

• Amoxicillin is the preferred first-line antibiotic—it is generally effective, inexpensive, and well-tolerated 1
• High-dose amoxicillin-clavulanate (875/125 mg twice daily) is recommended for patients at risk of resistant organisms, including those with recent antibiotic use, daycare exposure, age >65 years, or recent hospitalization 1

Alternative Antibiotics for Penicillin Allergy

• Doxycycline is the preferred alternative for penicillin-allergic adults 1
• Trimethoprim-sulfamethoxazole is an acceptable alternative 1
• Levofloxacin 500 mg once daily for 10-14 days or 750 mg once daily for 5 days is FDA-approved for acute bacterial sinusitis 2

Duration of Antibiotic Therapy

• Standard duration is 10-14 days or until symptom-free for 7 days 3
• 5-day regimens with higher-dose fluoroquinolones (levofloxacin 750 mg) are equally effective 2

Treatment Failure Management

If no improvement occurs after 3-5 days of initial antibiotic therapy, switch to a different antibiotic class: 1

• Consider broader-spectrum antibiotics such as high-dose amoxicillin-clavulanate or respiratory fluoroquinolones 1
• Evaluate for possible resistant pathogens or complications 1

Adjunctive Therapies

• Intranasal corticosteroids may be beneficial, especially when marked mucosal edema is present 1
• Short-term oral corticosteroids may be considered for patients who fail to respond to initial treatment 1
• Guaifenesin has theoretical benefits but insufficient evidence to support routine use 1

Medications to Avoid

• Antihistamines should be avoided unless the patient has concurrent allergic rhinitis, as they may thicken secretions and impair drainage 1
• Azithromycin and other macrolides are not recommended as first-line agents due to increasing resistance patterns 4

Red Flags Requiring Urgent Evaluation

Immediately refer or obtain imaging for: 1

• Orbital involvement (periorbital edema, vision changes, ophthalmoplegia)
• Intracranial complications (severe headache, altered mental status, meningeal signs)
• Severe unilateral facial pain or swelling
• Failure to respond to maximal medical therapy

Common Pitfalls to Avoid

• Overdiagnosis of bacterial sinusitis leading to unnecessary antibiotic use—most cases are viral and resolve spontaneously 1
• Prolonged use of topical decongestants (>3-5 days) causes rebound congestion (rhinitis medicamentosa) 1
• Using antihistamines in non-allergic patients thickens secretions and worsens drainage 1
• Failure to recognize complications such as orbital cellulitis or intracranial extension requiring urgent intervention 1

Special Considerations

• Recurrent sinusitis (≥3 episodes per year) warrants evaluation for underlying factors such as allergic rhinitis, immunodeficiency, or anatomical abnormalities 1
• Imaging is not recommended for uncomplicated acute sinusitis; reserve CT scanning for suspected complications or treatment failures 5
• Specialist referral is indicated for sinusitis refractory to standard antibiotic treatment, recurrent episodes, or suspected complications 1