What are the treatment options for upper respiratory tract infections (URTI) and sinusitis?

Treatment of Upper Respiratory Tract Infections and Sinusitis

Distinguishing Viral from Bacterial Sinusitis: The Critical First Step

Most URTIs (98-99.5%) are viral and resolve spontaneously within 7-10 days without antibiotics—only prescribe antibiotics when bacterial sinusitis is confirmed by specific clinical criteria. 1

Diagnose acute bacterial sinusitis only when one of three patterns is present:

• Persistent symptoms ≥10 days without improvement (nasal discharge, congestion, or cough) 2, 1
• Severe symptoms for ≥3 consecutive days: fever ≥39°C with purulent nasal discharge and facial pain 2, 1
• "Double sickening": worsening symptoms after initial improvement from a viral URI 2, 1

First-Line Antibiotic Treatment for Acute Bacterial Sinusitis

Adults

Amoxicillin remains the first-line antibiotic for uncomplicated acute bacterial sinusitis in adults. 2, 1

• Standard dosing: 500 mg twice daily for mild disease 1
• High-dose: 875 mg twice daily for moderate disease or areas with high S. pneumoniae resistance 2, 1
• Duration: 10-14 days or until symptom-free for 7 days 2, 1

For patients with recent antibiotic exposure or risk factors, start with high-dose amoxicillin-clavulanate 875/125 mg twice daily. 1 This provides coverage against β-lactamase-producing H. influenzae and M. catarrhalis, which have become increasingly prevalent. 1

Pediatric Patients (≥3 months)

• Standard-dose amoxicillin: 45 mg/kg/day divided into 2 doses 1
• High-dose amoxicillin: 80-90 mg/kg/day divided into 2 doses for children <2 years, daycare attendance, recent antibiotic use, or high local resistance 1
• High-dose amoxicillin-clavulanate: 80-90 mg/kg/day of amoxicillin component with 6.4 mg/kg/day clavulanate in 2 divided doses for children with risk factors 2, 1

Penicillin-Allergic Patients

For non-severe penicillin allergy (rash, mild reactions), second- or third-generation cephalosporins are safe and effective first-line alternatives. 1 The risk of cross-reactivity is negligible. 1

Preferred options:

• Cefuroxime-axetil (second-generation cephalosporin) 2, 1
• Cefpodoxime-proxetil (third-generation, superior H. influenzae coverage) 2, 1
• Cefdinir (third-generation, excellent coverage) 2, 1

For documented severe Type I hypersensitivity (anaphylaxis), use respiratory fluoroquinolones: levofloxacin 500 mg once daily or moxifloxacin 400 mg once daily for 10-14 days. 1

Critical Pitfall to Avoid

Never use azithromycin or other macrolides as first-line therapy—resistance rates exceed 20-25% for both S. pneumoniae and H. influenzae. 1, 3 French and American guidelines explicitly exclude macrolides from recommended therapy due to resistance prevalence. 1

Treatment Failure Protocol

Reassess patients at 3-5 days (adults) or 72 hours (pediatrics)—if no improvement, switch antibiotics immediately. 2, 1

Second-Line Options After Amoxicillin Failure

Switch to high-dose amoxicillin-clavulanate 875/125 mg twice daily (adults) or 90 mg/kg/day amoxicillin component (pediatrics). 2, 1 This covers β-lactamase-producing organisms and drug-resistant S. pneumoniae. 1

If amoxicillin-clavulanate fails or patient has severe penicillin allergy, use respiratory fluoroquinolones: levofloxacin 500-750 mg once daily or moxifloxacin 400 mg once daily for 10 days. 1 These provide 90-92% predicted clinical efficacy against multi-drug resistant organisms. 1

Alternative for Treatment Failures

Ceftriaxone 1-2 g IM/IV once daily for 5 days (adults) or 50 mg/kg once daily (pediatrics) is indicated when oral antibiotics fail or patient cannot tolerate oral medications. 1 This achieves 90-92% clinical efficacy with once-daily dosing that improves compliance. 1

Sinusitis by Anatomic Location

Maxillary Sinusitis (Most Common)

Use standard first-line antibiotics as outlined above. 2, 1 Symptoms include unilateral/bilateral infraorbital pain worsening when bending forward, pulsatile, peaking evening/night. 1

Frontal, Ethmoidal, or Sphenoidal Sinusitis

Reserve fluoroquinolones (levofloxacin 500 mg or moxifloxacin 400 mg once daily) for these locations due to potential for serious complications. 2, 1 These sites require more aggressive therapy and may necessitate hospitalization for parenteral antibiotics. 2

Adjunctive Therapies

Intranasal corticosteroids (mometasone, fluticasone, or budesonide twice daily) should be used as adjunct to antibiotic therapy—they reduce mucosal inflammation and improve symptom resolution. 2, 1 Strong evidence from multiple RCTs supports this recommendation. 1

Short-term oral corticosteroids (typically 5 days) are reasonable for patients who fail initial treatment, have nasal polyposis, or demonstrate marked mucosal edema. 2, 1 However, never give systemic corticosteroids without antibiotics when bacterial sinusitis is suspected, as this may suppress immune response and allow bacterial proliferation. 1

Symptomatic Measures

• Adequate hydration and rest 2
• Analgesics (acetaminophen, NSAIDs) for pain 2, 1
• Warm facial packs 2
• Saline nasal irrigation for symptomatic relief 1
• Sleeping with head elevated 2
• Decongestants (systemic or topical) as needed 1

Special Considerations and When to Refer

Refer to otolaryngology or allergist-immunologist when:

• Symptoms refractory to two courses of appropriate antibiotics 1
• Recurrent sinusitis (≥3 episodes per year) 2, 1
• Suspected complications (orbital cellulitis, meningitis) 1
• Need for sinus aspiration/culture in immunocompromised patients 1
• Evaluation for underlying allergic rhinitis, immunodeficiency, or anatomic abnormalities 2, 1

Critical Pitfalls to Avoid

Do not prescribe antibiotics for viral rhinosinusitis lasting <10 days—this contributes to antimicrobial resistance without clinical benefit. 1 Wait at least 10 days before considering antibiotics unless severe symptoms are present. 1

Do not use mucus color alone to determine antibiotic need—purulent discharge reflects neutrophils, not necessarily bacteria. 1

Ensure adequate treatment duration (minimum 5-10 days, typically 10-14 days) to prevent relapse. 2, 1 Some cephalosporins are effective in 5-day courses, but standard therapy remains 7-10 days. 2, 1

Reserve fluoroquinolones for treatment failures, complicated sinusitis, or severe penicillin allergy—overuse promotes resistance. 2, 1