What is the recommended treatment for acute rhinosinusitis?

Acute Rhinosinusitis Treatment

For acute rhinosinusitis, reserve antibiotics only for patients with persistent symptoms >10 days, severe symptoms (fever >39°C with purulent discharge and facial pain for ≥3 consecutive days), or worsening after initial improvement ("double sickening"), and use amoxicillin-clavulanate as first-line antibiotic therapy when indicated. 1

Distinguishing Viral from Bacterial Rhinosinusitis

The critical first step is determining whether antibiotics are warranted, as most acute rhinosinusitis is viral and self-limited:

• Viral rhinosinusitis presents with symptoms lasting <10 days that gradually improve, without high fever or severe purulent discharge 2
• Acute bacterial rhinosinusitis (ABRS) requires one of three specific patterns 3, 1:
  • Persistent symptoms for ≥10 days without improvement 1, 2
  • Severe symptoms: fever >39°C (102.2°F), purulent nasal discharge, and facial pain for ≥3 consecutive days 1, 2
  • "Double sickening": initial improvement followed by worsening symptoms (new fever ≥38°C or substantially worse nasal discharge/cough) after 5 days 3, 1, 2

Critical pitfall to avoid: Purulent (colored) nasal discharge alone does NOT indicate bacterial infection—it reflects neutrophil presence that occurs in both viral and bacterial infections 2. The yellow-green color comes from inflammatory cells and enzymes, not bacteria 2. Only 1 in 15 patients with viral upper respiratory infections develop true bacterial sinusitis 2.

Initial Management for Viral Rhinosinusitis (Symptoms <10 Days)

Most patients should receive symptomatic treatment only, without antibiotics 3:

• Analgesics/antipyretics (acetaminophen, ibuprofen, or NSAIDs) for pain or fever 3, 4
• Intranasal saline irrigation with physiologic or hypertonic saline for symptom relief and cleansing 3, 1
• Intranasal corticosteroids provide modest benefit (number needed to treat = 14), particularly in patients with allergic rhinitis 3, 1
• Oral or topical decongestants may provide relief, but limit topical use to 3-5 days maximum to avoid rebound congestion 3, 4

Therapies to avoid: Antihistamines in non-atopic patients, guaifenesin, and systemic steroids lack evidence for benefit in acute viral rhinosinusitis 3.

Antibiotic Therapy for Confirmed ABRS

First-Line Antibiotic Choice

Amoxicillin-clavulanate is the preferred first-line agent 1, though some guidelines accept amoxicillin alone 3:

• Standard-dose amoxicillin-clavulanate for mild disease without risk factors for resistant pathogens 1
• High-dose amoxicillin-clavulanate for areas with high penicillin-resistant S. pneumoniae prevalence, moderate disease severity, or risk factors for resistance (antibiotic use within 4-6 weeks) 1
• Recent evidence shows amoxicillin alone is as effective as amoxicillin-clavulanate for uncomplicated ABRS 5, though amoxicillin-clavulanate provides broader coverage for β-lactamase-producing H. influenzae and M. catarrhalis 3, 1

Alternative Antibiotics for Penicillin Allergy

For patients with β-lactam allergy 1, 5:

• Doxycycline (preferred alternative) 3, 6
• Respiratory fluoroquinolones (levofloxacin or moxifloxacin) 3, 1
• Trimethoprim-sulfamethoxazole for mild disease only 6

For children with non-type I hypersensitivity: clindamycin plus a third-generation cephalosporin 5

Treatment Duration

• Adults: 5-7 days for uncomplicated ABRS 1, 7
• Children: 10-14 days 1
• Alternative regimen: Continue until symptom-free for 7 additional days 4, 8

Watchful Waiting Option

The American Academy of Otolaryngology-Head and Neck Surgery recommends watchful waiting (without immediate antibiotics) as an appropriate initial strategy for uncomplicated ABRS with mild symptoms 1, provided reliable follow-up is assured 3. This approach acknowledges that even bacterial sinusitis often resolves spontaneously 3.

Adjunctive Therapies for ABRS

Continue symptomatic treatments alongside antibiotics 3, 1:

• Intranasal saline irrigation (weak recommendation) 1
• Intranasal corticosteroids, especially with concurrent allergic rhinitis (weak recommendation) 1
• Analgesics for pain relief 3

Do NOT use: Oral antihistamines or decongestants lack evidence for benefit in ABRS (strong recommendation against) 3.

When to Escalate or Refer

Reassess after 3-5 days of antibiotic therapy 4:

• If improving: continue current treatment to completion 4
• If not improving: switch to broader-spectrum antibiotics (high-dose amoxicillin-clavulanate, cefuroxime, cefpodoxime, or fluoroquinolones) 4

Refer to specialist (otolaryngologist, infectious disease, or allergist) for 3, 1:

• Seriously ill or immunocompromised patients 1
• Clinical deterioration despite appropriate antibiotic therapy 3, 1
• Recurrent episodes 3, 1
• Suspected complications (periorbital edema, diplopia, severe headache, altered mental status) 2

Key Evidence-Based Principles

The number needed to treat with antibiotics is 18 for one patient to be cured rapidly, while the number needed to harm from adverse effects is only 8 3. This unfavorable benefit-harm ratio underscores why antibiotics should be reserved for patients meeting specific diagnostic criteria for ABRS, not prescribed routinely for all acute rhinosinusitis 3.

Imaging is not recommended for uncomplicated acute rhinosinusitis due to high false-positive and false-negative rates 4, 2. Reserve CT scanning for suspected complications or when surgical intervention is being considered 9.