What antibiotics are recommended for acute rhinosinusitis?

Antibiotic Recommendations for Acute Rhinosinusitis

For acute bacterial rhinosinusitis (ABRS), amoxicillin-clavulanate is the preferred first-line antibiotic, with amoxicillin as an acceptable alternative in mild cases without risk factors for resistant organisms. 1

When to Use Antibiotics

Antibiotics should only be prescribed for patients with:

• Persistent symptoms for more than 10 days without improvement
• Severe symptoms (fever >39°C, purulent nasal discharge, facial pain) for at least 3 consecutive days
• Worsening symptoms following initial improvement ("double sickening") 1

Most cases of acute rhinosinusitis are viral and self-limited, with antibiotics providing minimal benefit while increasing risk of adverse effects (number needed to treat: 18; number needed to harm: 8). 1

First-Line Antibiotic Options

Adults:

• Amoxicillin-clavulanate (preferred by IDSA guidelines)
  • Standard dose: 875/125 mg twice daily
  • High dose: 2000/125 mg twice daily (for areas with high S. pneumoniae resistance or patients with risk factors) 1
• Amoxicillin
  • Standard dose: 1.5 g/day divided
  • High dose: 4 g/day divided (for high-risk patients) 1

Children:

• Amoxicillin-clavulanate (90 mg/6.4 mg/kg per day) 1
• Amoxicillin (45-90 mg/kg/day) 1

Alternative Options (Penicillin Allergy)

Non-Type I Hypersensitivity (e.g., rash):

• Cephalosporins (cefdinir, cefpodoxime proxetil, or cefuroxime axetil) 1

Type I Hypersensitivity (anaphylaxis):

• Doxycycline (adults only) 1
• Respiratory fluoroquinolones (levofloxacin or moxifloxacin) - reserve for adults with treatment failures or severe allergies 1, 2
• TMP-SMX, macrolides, or azithromycin (less effective options with 20-25% failure rates) 1

Risk Factors for Resistant Organisms

Consider high-dose amoxicillin-clavulanate if any of these factors are present:

• Antibiotic use in the past month
• Contact with treated individuals or healthcare environment
• Prior antibiotic failure
• Age >65 years
• Daycare attendance (or household contact)
• High local prevalence of resistant bacteria
• Immunocompromised state
• Comorbidities (diabetes, chronic cardiac/hepatic/renal disease) 1

Duration of Therapy

• Traditional course: 10-14 days
• Shorter courses (5-7 days) may be equally effective with fewer side effects 1
• Some recommend continuing therapy until symptom-free plus an additional 7 days 3

Treatment Failure

If no improvement after 72 hours of appropriate antibiotic therapy:

1. Reevaluate diagnosis
2. Consider switching to broader-spectrum antibiotic
3. For initial amoxicillin: switch to amoxicillin-clavulanate
4. For initial amoxicillin-clavulanate: consider respiratory fluoroquinolone or specialist referral 1, 4

Adjunctive Therapies

These may provide symptomatic relief and potentially decrease antibiotic need:

• Intranasal saline irrigation
• Intranasal corticosteroids
• Analgesics for pain
• Antipyretics for fever
• Decongestants (systemic or topical)
• Mucolytics
• Antihistamines (if allergic component) 1

Common Pitfalls

1. Overdiagnosis of bacterial infection: Most rhinosinusitis cases are viral; reserve antibiotics for those meeting specific criteria
2. Premature antibiotic switch: Allow 72 hours for response before changing therapy
3. Inadequate dosing: Use high-dose regimens for patients with risk factors for resistant organisms
4. Inappropriate fluoroquinolone use: Reserve these for treatment failures or true penicillin allergies to minimize resistance development
5. Neglecting adjunctive therapies: Supportive care is essential and may reduce antibiotic need

Remember that acute rhinosinusitis is usually self-limited, and antibiotics should be prescribed judiciously to minimize adverse effects and antibiotic resistance.