What is the treatment for sinus infection?

Treatment for Sinus Infection

For acute bacterial sinusitis, amoxicillin or amoxicillin-clavulanate for 10-14 days is the first-line treatment, combined with adjunctive measures like saline irrigation and intranasal corticosteroids to facilitate drainage. 1

Distinguishing Acute vs. Chronic Sinusitis

The treatment approach differs fundamentally based on duration:

• Acute sinusitis: Symptoms present for ≤4 weeks, primarily bacterial (S. pneumoniae, H. influenzae, M. catarrhalis) 1
• Chronic sinusitis: Symptoms present for ≥3 months, controversial bacterial role, surgery often needed 1, 2

When to Start Antibiotics for Acute Sinusitis

Do not prescribe antibiotics for every patient with nasal symptoms. Antibiotics are indicated only when: 3, 4

• Persistent symptoms: Nasal discharge or cough lasting >10 days without improvement 3
• Severe symptoms: High fever (≥39°C) with purulent nasal discharge for 3-4 consecutive days 3
• Worsening symptoms: Initial improvement followed by deterioration ("double-sickening") 3
• Unilateral maxillary sinusitis with associated dental infection 1

Critical pitfall: Most acute sinusitis cases are viral and resolve without antibiotics—patients with symptoms <7 days likely have viral infection and should receive symptomatic treatment only. 4

First-Line Antibiotic Therapy for Acute Sinusitis

Standard Acute Maxillary Sinusitis

Amoxicillin 500 mg twice daily for 10-14 days is the gold standard empiric therapy. 1 Alternative first-line options include: 1

• Amoxicillin-clavulanate (500-875 mg twice daily): Preferred when β-lactamase-producing organisms suspected (up to 20% of H. influenzae, 50-70% of M. catarrhalis) 1
• Second-generation cephalosporins: Cefuroxime-axetil (effective in 5 days) 1
• Third-generation cephalosporins: Cefpodoxime-proxetil, cefotiam-hexetil 1
• Pristinamycin: For penicillin allergy 1

Expected clinical response rate: 70-80% 1

High-Risk Sinusitis (Frontal, Ethmoidal, Sphenoidal)

These locations carry higher complication risk (meningitis, intracranial abscess). Reserve fluoroquinolones with pneumococcal activity (levofloxacin, moxifloxacin) for these cases or treatment failures. 1 These patients require hospitalization if complications suspected (meningeal signs, exophthalmos, palpebral edema, severe pain). 1

Penicillin-Allergic Patients

• Cephalosporins: Cefuroxime-axetil, cefpodoxime-proxetil, cefprozil 2
• Fluoroquinolones: Levofloxacin, moxifloxacin (second-line to prevent resistance) 2
• Macrolide/sulfonamide combinations: Erythromycin-sulfisoxazole or trimethoprim-sulfamethoxazole 1

Critical warning: Azithromycin should NOT be used due to high resistance rates in S. pneumoniae and H. influenzae. 2, 5 Despite FDA approval for acute bacterial sinusitis at 500 mg daily for 3 days 5, guideline evidence strongly advises against its use. 2

Treatment for Chronic Sinusitis

Antibiotics are NOT the primary treatment for chronic sinusitis. 2, 6 The role of bacterial infection is controversial, and routine antibiotic use is unsupported. 2

When Antibiotics Are Indicated

Only use antibiotics for acute bacterial exacerbations superimposed on chronic sinusitis, not as maintenance therapy. 2 When prescribed:

• Minimum 3-week course targeting H. influenzae, anaerobes, and S. pneumoniae 2
• First-line: Amoxicillin (500 mg twice daily) or amoxicillin-clavulanate (500-875 mg twice daily) 2
• Penicillin allergy: Cephalosporins or fluoroquinolones 2

Primary Treatment Modalities

Intranasal corticosteroids are the cornerstone of chronic sinusitis management due to anti-inflammatory effects and documented efficacy. 6 Combined medical and surgical treatment achieves >60% cure rate at 3 years. 1

Essential Adjunctive Therapies (All Types)

These facilitate drainage and improve outcomes when combined with antibiotics:

Saline Irrigation

Hypertonic saline irrigation prevents crusting and improves mucociliary clearance more effectively than normal saline. 1, 6 This should be continued long-term in recurrent disease. 7

Decongestants

• Oral decongestants: Widen ostia and reduce turbinate swelling 6
• Topical decongestants (oxymetazoline): Limit to 3-5 days maximum to prevent rebound congestion 2

Intranasal Corticosteroids

Particularly beneficial for patients with allergic rhinitis component or chronic sinusitis. 6, 8 Flunisolide decreases inflammation and promotes drainage. 8

Avoid Routine Use

• Antihistamines: Only indicated if allergic rhinitis is active during treatment 9
• Guaifenesin/expectorants: Insufficient evidence for efficacy in sinusitis 1

Special Populations Requiring Evaluation

Recurrent or Refractory Cases

Evaluate for underlying conditions: 2, 6

• Allergic rhinitis: Test for IgE sensitization to inhalant allergens 2
• Immunodeficiency: Check quantitative IgG, IgA, IgM levels and specific antibody responses 2
• Anatomic abnormalities: CT imaging if not already performed 2
• Other conditions: Vasculitides, granulomatous diseases, cystic fibrosis, GERD 2, 6

Immunodeficiency

IVIG is approved for antibody deficiency disorders (X-linked agammaglobulinemia, common variable immunodeficiency, Wiskott-Aldrich syndrome, hyper-IgM syndrome) and can prevent life-threatening complications including meningitis, sepsis, and death. 1

Common Pitfalls to Avoid

• Never use antibiotic prophylaxis for chronic sinusitis—no evidence supports this approach 2
• Never prescribe antibiotics for viral upper respiratory infections 2
• Never use macrolides (azithromycin, clarithromycin) as first-line therapy due to weak activity against resistant organisms 2
• Never extend topical decongestants beyond 5 days 2
• Never reserve fluoroquinolones for routine first-line use—use as second-line agents to prevent resistance 2
• Never diagnose acute bacterial sinusitis in patients with symptoms <7 days—likely viral 4