What is the treatment for sinusitis?

Treatment for Sinusitis

Amoxicillin at 1.5-4 g/day for 10-14 days is the first-line antibiotic treatment for acute bacterial sinusitis in adults, with high-dose amoxicillin-clavulanate (4 g/250 mg per day) reserved for treatment failures or moderate disease. 1

Initial Assessment and Diagnosis

• Acute sinusitis is defined as symptoms lasting less than 4 weeks, with typical presentations including persistent symptoms beyond 10 days, severe symptoms with high fever and purulent discharge for 3-4 consecutive days, or worsening after initial improvement 2, 3
• Key symptoms to identify include nasal congestion, purulent rhinorrhea, postnasal drip, facial or dental pain, headache, and cough 1
• Diagnosis is primarily clinical based on history and physical examination, though imaging may enhance diagnostic certainty in adults and older children (>6 years) 2, 3

First-Line Antibiotic Therapy

For Mild Disease (No Recent Antibiotics)

• Amoxicillin 1.5-4 g/day is the preferred initial choice due to effectiveness, low cost, and tolerability 2, 1
• Alternative first-line options include amoxicillin-clavulanate (1.75 g/250 mg per day), cefpodoxime, cefuroxime axetil, or cefdinir 2
• For penicillin-allergic patients, trimethoprim-sulfamethoxazole can be used in adults, though resistance is more common in children 2
• Macrolides (azithromycin, clarithromycin) or doxycycline may be considered for β-lactam allergies, but bacteriologic failure rates of 20-25% are possible 2

For Moderate Disease or Recent Antibiotic Use (Within 4-6 Weeks)

• High-dose amoxicillin-clavulanate (4 g/250 mg per day) or respiratory fluoroquinolones (levofloxacin, moxifloxacin, gatifloxacin) are recommended 2, 1
• These regimens achieve 90-92% predicted clinical efficacy compared to 62% spontaneous resolution in untreated adults 2
• Ceftriaxone 1 g/day IM or IV for 5 days is an alternative option 2

Pediatric Dosing

• For acute bacterial sinusitis in children: azithromycin 10 mg/kg once daily for 3 days 4
• High-dose amoxicillin-clavulanate (90 mg/6.4 mg per kg per day) achieves 91-92% predicted efficacy in children 2

Duration of Treatment

• Standard treatment duration is 10-14 days, with some clinicians continuing until near-complete symptom resolution 2, 1
• Azithromycin offers a shorter 3-day course option (500 mg daily) 4

Adjunctive Therapies

Intranasal Corticosteroids

• Nasal corticosteroids are helpful as adjunctive therapy for reducing inflammation and mucosal edema in both acute and chronic sinusitis 2, 1
• Particularly beneficial in patients with allergic rhinitis, nasal polyposis, or marked mucosal edema 2

Supportive Measures

• Adequate hydration, rest, analgesics, warm facial compresses, steam inhalation, and sleeping with head elevated 2, 1
• Saline irrigation prevents crusting and facilitates mechanical mucus removal 5
• Oral and topical decongestants may provide symptomatic relief but should be used cautiously 2, 5

Management of Treatment Failure

Reassessment at 3-5 Days

• Patients should be instructed to call if symptoms worsen (especially with headache or high fever) or fail to improve within 3-5 days 2, 1

Partial Response (Improved but Not Resolved)

• Continue current antibiotic for an additional 10-14 days, or switch to broader-spectrum coverage 2, 1

Poor Response (Little to No Improvement at 72 Hours)

• Switch to high-dose amoxicillin-clavulanate, cefuroxime, cefpodoxime, cefdinir, or respiratory fluoroquinolones 2, 1
• For failures after 21-28 days, consider broader-spectrum agents with or without anaerobic coverage (clindamycin or metronidazole) 2
• Consider sinus CT scan if not already performed 2

Common Pitfalls to Avoid

• Do not use antibiotics for viral upper respiratory infections - reserve for symptoms lasting >7-10 days or severe presentations 3
• Avoid overuse of respiratory fluoroquinolones for mild disease, as this promotes resistance 2
• Do not overlook underlying conditions such as allergic rhinitis, which predisposes to sinusitis and requires concurrent treatment 2, 1
• Ensure adequate antibiotic dosing - standard-dose amoxicillin may be insufficient in areas with high resistance 2

When to Refer to Specialist

• Sinusitis refractory to 21-28 days of appropriate antibiotic therapy 2, 1
• Recurrent sinusitis (≥3 episodes per year) 2, 1
• Suspected complications, immunodeficiency, structural abnormalities, or nasal polyps 2, 1
• Consider allergist-immunologist for underlying allergic factors and unusual pathogens 2
• Consider otolaryngologist for structural abnormalities 2

Chronic Sinusitis (Symptoms >12 Weeks)

• Intranasal corticosteroids are the cornerstone of treatment for chronic sinusitis due to anti-inflammatory effects 5
• Longer antibiotic courses may be required for chronic infectious sinusitis, with attention to anaerobic pathogens 5
• Antibiotics should not be primary treatment for non-infectious chronic sinusitis 5
• Evaluate and treat underlying conditions including allergic rhinitis, GERD, and immunodeficiency 5