What is the initial antibiotic choice for sinusitis?

Initial Antibiotic Choice for Sinusitis

Amoxicillin-clavulanate is the recommended first-line antibiotic treatment for acute bacterial sinusitis, with a dosage of 875/125 mg twice daily for 5-7 days in adults. 1

Diagnosis of Acute Bacterial Sinusitis

Before initiating antibiotics, confirm the diagnosis of acute bacterial sinusitis based on one of these clinical presentations:

• Persistent symptoms: Nasal discharge or cough for >10 days without improvement
• Severe symptoms: High fever (>39°C/102.2°F) with purulent nasal discharge or facial pain for ≥3 consecutive days
• Worsening symptoms: Initial improvement followed by worsening nasal discharge, cough, or fever 1

First-Line Antibiotic Treatment

• Amoxicillin-clavulanate: 875/125 mg twice daily for 5-7 days

  • Preferred over amoxicillin alone due to increasing prevalence of beta-lactamase-producing pathogens 1
  • High-dose option: 2000 mg (amoxicillin component) with 125 mg clavulanate twice daily for 5-7 days in areas with high S. pneumoniae resistance 1

• Amoxicillin: 500-875 mg three times daily for 5-7 days

  • May be used in areas with low resistance patterns 1

Alternative Antibiotics for Penicillin Allergy

For patients with non-severe penicillin allergy:

• Cefdinir: 300-600 mg twice daily for 5-7 days
• Cefuroxime: 250-500 mg twice daily for 5-7 days
• Cefpodoxime: 200-400 mg twice daily for 5-7 days 1

For patients with severe penicillin allergy:

• Levofloxacin: 500 mg once daily for 5-7 days 1, 2
• Moxifloxacin: 400 mg once daily for 5-7 days 1, 3
• Doxycycline: Alternative for patients who cannot take fluoroquinolones 1

Duration of Treatment

• Standard duration: 5-7 days for uncomplicated cases in adults
• Extended duration: 10-14 days may be considered for more severe or complicated cases 1

Adjunctive Treatments

In addition to antibiotics, consider:

• Intranasal corticosteroids: Reduce inflammation
• Saline nasal irrigation: Helps clear mucus and reduce inflammation
• Short-term nasal decongestants: May provide symptomatic relief but avoid prolonged use 1

Monitoring and Follow-up

• Assess for clinical improvement within 72 hours of starting antibiotics
• If no improvement is seen after 72 hours, consider switching to a broader-spectrum antibiotic
• Refer to an otolaryngologist if symptoms persist despite appropriate antibiotic therapy and adjunctive treatments 1

Important Considerations

• Reserve antibiotics for confirmed bacterial sinusitis; viral sinusitis does not benefit from antibiotics
• Consider local resistance patterns when selecting initial therapy
• Fluoroquinolones (levofloxacin, moxifloxacin) should be reserved for patients with penicillin allergy or treatment failures due to concerns about antimicrobial resistance and side effects
• Surgical intervention may be necessary for persistent symptoms beyond 3 weeks despite appropriate antibiotic therapy 1