What is the next step for a patient with a sinus infection not improving with Augmentin (amoxicillin-clavulanate)?

Management of Sinus Infection Not Improving with Augmentin

If your patient has failed to improve after 7 days of Augmentin for acute bacterial rhinosinusitis, you should switch to a respiratory fluoroquinolone (levofloxacin or moxifloxacin) for 5-7 days. 1

Reassess the Patient First

Before changing antibiotics, you must confirm the diagnosis and rule out complications 2:

• Verify true treatment failure: Worsening symptoms at any time OR lack of improvement by 7 days after starting Augmentin constitutes treatment failure 2
• Confirm acute bacterial rhinosinusitis: Look for purulent nasal drainage with either nasal obstruction, facial pain/pressure/fullness, or both 2
• Exclude complications: Assess for periorbital edema, severe headache, visual changes, or altered mental status that would require urgent imaging and specialist referral 2
• Rule out alternative diagnoses: Consider dental infections, nasal polyps, sinonasal tumors, or non-infectious causes 3

First-Line Antibiotic Change

Switch to a respiratory fluoroquinolone 1:

• Levofloxacin 500-750 mg once daily for 5-7 days OR moxifloxacin 400 mg once daily for 5-7 days 1
• These provide excellent coverage for both S. pneumoniae and H. influenzae, including resistant strains that may have caused Augmentin failure 1

Alternative Option (If Fluoroquinolones Contraindicated)

High-dose amoxicillin-clavulanate can be considered as an alternative 3, 1:

• 2000 mg amoxicillin with 125 mg clavulanate twice daily for 10-14 days 3, 1
• However, recent high-quality evidence shows this may not be superior to standard dosing and causes significantly more severe diarrhea (15.8% vs 4.8%) 4
• The 2021 JAMA trial found no benefit of high-dose over standard-dose Augmentin 5

What NOT to Use

Avoid these antibiotics as second-line agents 1:

• Macrolides (azithromycin, clarithromycin): Poor activity against penicillin-resistant H. influenzae and S. pneumoniae 1
• Cefixime or ceftibuten: Inadequate coverage of S. pneumoniae 1

Essential Adjunctive Therapies

Add these regardless of antibiotic choice 3, 1:

• Intranasal corticosteroids (e.g., fluticasone, mometasone): Reduce mucosal inflammation 3, 1
• Saline nasal irrigation: Improves sinus drainage and mucociliary clearance 3, 1
• Consider short-term oral corticosteroids if marked mucosal edema or nasal polyps are present 3

Monitor Response to New Treatment

Expect improvement within 3-5 days 1:

• If symptoms worsen after 48-72 hours OR fail to improve after 3-5 days on the fluoroquinolone, further evaluation is mandatory 2, 1
• At this point, consider CT imaging to assess for anatomical abnormalities, extent of disease, or complications 3, 1

When to Refer to a Specialist

Refer to ENT or allergy/immunology if 2, 3, 1:

• Patient fails to respond to the respiratory fluoroquinolone 1
• Recurrent sinusitis (≥3 episodes per year) 1
• Suspected structural abnormalities, nasal polyps, or immunodeficiency 3
• Unusual opportunistic infections or significant impact on quality of life 2

Common Pitfalls to Avoid

• Don't wait too long to reassess: The 7-day cutpoint for treatment failure is evidence-based; don't extend initial therapy beyond this without reassessment 2
• Don't obtain imaging routinely: CT is not indicated for uncomplicated acute bacterial rhinosinusitis unless complications are suspected or the patient fails appropriate antibiotic therapy 2, 3
• Don't assume compliance: Verify the patient actually took the Augmentin as prescribed before labeling it a treatment failure 3
• Don't ignore underlying factors: Allergic rhinitis, GERD, and anatomical abnormalities can perpetuate sinusitis despite appropriate antibiotics 2, 3