What is the treatment for a sinus infection?

Treatment of Sinus Infection

Amoxicillin 500 mg twice daily (or 875 mg twice daily for more severe infections) for 10-14 days is the first-line treatment for acute bacterial sinusitis in adults. 1, 2

Distinguishing Bacterial from Viral Sinusitis

Before prescribing antibiotics, confirm bacterial infection by identifying one of three patterns: 1, 3

• Persistent symptoms ≥10 days without clinical improvement 1, 3
• Severe symptoms (fever ≥39°C with purulent nasal discharge) for ≥3 consecutive days 1, 3
• "Double sickening" - worsening symptoms after initial improvement from a viral upper respiratory infection 1, 3

Critical caveat: 98-99.5% of acute rhinosinusitis is viral and resolves spontaneously within 7-10 days without antibiotics. 1 Wait at least 10 days before considering antibiotics unless severe symptoms are present. 1

First-Line Antibiotic Treatment

Standard Therapy

• Amoxicillin 500 mg twice daily for mild disease 1, 2
• Amoxicillin 875 mg twice daily for moderate disease 1, 2
• Duration: 10-14 days or until symptom-free for 7 days 1, 2
• Take with food to reduce gastrointestinal upset 4

High-Risk Patients

For patients with recent antibiotic exposure, age <2 years, daycare attendance, or areas with high prevalence of resistant Streptococcus pneumoniae, use: 1, 2

• Amoxicillin-clavulanate 875 mg/125 mg twice daily for adults 1, 2
• Pediatric dosing: 80-90 mg/kg/day of amoxicillin component with 6.4 mg/kg/day clavulanate in 2 divided doses 1

Penicillin-Allergic Patients

Non-Severe Allergy (Rash, Mild Reactions)

Second- or third-generation cephalosporins are safe and effective: 1, 2

• Cefuroxime-axetil (second-generation) 1, 2
• Cefpodoxime-proxetil (third-generation, superior activity against H. influenzae) 1, 2
• Cefdinir (third-generation) 1, 2

Severe Penicillin Allergy (Anaphylaxis)

• Levofloxacin 500 mg once daily for 10-14 days 1, 2
• Moxifloxacin 400 mg once daily for 10 days 1

Important: Reserve fluoroquinolones for severe allergies or treatment failures to prevent resistance development. 1

Do NOT use azithromycin - resistance rates exceed 20-25% for both S. pneumoniae and H. influenzae. 1

Second-Line Treatment for Treatment Failure

If no improvement after 3-5 days of initial therapy: 1, 2

First Option: High-Dose Amoxicillin-Clavulanate

• Adults: 875 mg/125 mg twice daily or 2 g/125 mg twice daily 1, 2
• Pediatrics: 90 mg/kg/day amoxicillin component with 6.4 mg/kg/day clavulanate in 2 divided doses 1

Second Option: Respiratory Fluoroquinolones

• Levofloxacin 500-750 mg once daily for 10-14 days 1
• Moxifloxacin 400 mg once daily for 10 days 1
• Predicted clinical efficacy: 90-92% against drug-resistant organisms 1

Third Option: Ceftriaxone (Parenteral)

For patients unable to tolerate oral medications or with severe disease: 1

• Adults: 1-2 g IM or IV once daily for 5 days 1
• Pediatrics: 50 mg/kg IM or IV once daily for 5 days 1

Adjunctive Therapies

Intranasal Corticosteroids (Strongly Recommended)

• Mometasone, fluticasone, or budesonide twice daily 1, 2, 5
• Reduces mucosal inflammation and improves symptom resolution 1, 2
• Use as adjunct to antibiotic therapy in both acute and chronic sinusitis 1, 2, 5

Oral Corticosteroids (Short-Term Use Only)

Consider for patients with: 1, 2

• Marked mucosal edema 1, 2
• Failure to respond to initial antibiotic treatment 1, 2
• Nasal polyposis 1
• Typical duration: 5 days 1

Critical warning: Never give systemic corticosteroids without antibiotics when bacterial sinusitis is suspected, as this may suppress immune response and allow bacterial proliferation. 1

Supportive Care

• Saline nasal irrigation for mechanical removal of mucus 2, 5, 3
• Analgesics (acetaminophen, NSAIDs) for pain relief 1, 2
• Decongestants (systemic or topical) - limit topical use to ≤5 days to avoid rebound congestion 1, 2
• Adequate hydration, warm facial packs, sleeping with head elevated 1, 2

Special Situations

Frontal, Ethmoidal, or Sphenoidal Sinusitis

These locations carry higher risk of complications and require broader coverage: 1, 2

• Levofloxacin 500 mg once daily or moxifloxacin 400 mg once daily 1, 2

Sinusitis of Dental Origin

Antibiotic therapy is definitely indicated. 2

Chronic Sinusitis (Symptoms ≥12 Weeks)

• Intranasal corticosteroids are the cornerstone of treatment 5, 6
• Saline irrigation to prevent crusting and facilitate mucus removal 5, 6
• Antibiotics play a controversial role unless clear evidence of bacterial infection 5, 6
• Longer duration of antibiotic therapy may be required, with attention to anaerobic pathogens 5

When to Reassess and Escalate

• Reassess at 3-5 days: If no improvement, switch antibiotics or re-evaluate diagnosis 1, 2
• Reassess at 7 days: Confirm diagnosis if symptoms persist or worsen 1
• Refer to otolaryngology if: 1, 3, 6
  • Symptoms refractory to two courses of appropriate antibiotics 1
  • Recurrent sinusitis (≥3 episodes per year) 1
  • Suspected complications (orbital cellulitis, meningitis) 1
  • Need for sinus aspiration/culture in immunocompromised patients 1

Critical Pitfalls to Avoid

• Do NOT prescribe antibiotics for viral rhinosinusitis lasting <10 days unless severe symptoms are present 1, 3
• Do NOT use mucus color alone to determine antibiotic need - color reflects neutrophils, not bacteria 1
• Complete the full course of antibiotics even after symptoms improve to prevent relapse and resistance 1, 4
• Avoid fluoroquinolone overuse - reserve for treatment failures, severe disease, or documented allergies 1, 2
• Do NOT use azithromycin as first-line therapy due to high resistance rates 1, 7
• Limit topical decongestants to ≤5 days to avoid rhinitis medicamentosa 2