What are the treatment options for sinusitis?

Sinusitis Treatment

Distinguishing Viral from Bacterial Sinusitis is Critical

Most acute rhinosinusitis (98-99.5%) is viral and resolves spontaneously within 7-10 days without antibiotics—reserve antibiotics only for confirmed bacterial sinusitis to avoid unnecessary adverse effects and antimicrobial resistance. 1, 2

Diagnose bacterial sinusitis only when symptoms meet one of three criteria: 1, 2

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

First-Line Antibiotic Treatment for Acute Bacterial Sinusitis

Standard First-Line Therapy

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

Adult dosing: 1, 2

• Mild disease: 500 mg twice daily for 10-14 days
• Moderate disease: 875 mg twice daily for 10-14 days
• High-dose for resistant organisms: 1.5-4 g/day divided into doses

Pediatric dosing: 2

• Standard: 45 mg/kg/day in 2 divided doses
• High-dose (for age <2 years, daycare attendance, recent antibiotic use, or high local resistance): 80-90 mg/kg/day in 2 divided doses

When to Escalate to Amoxicillin-Clavulanate

Switch to high-dose amoxicillin-clavulanate if no improvement after 3-5 days of amoxicillin therapy. 1, 2 This provides coverage against β-lactamase-producing Haemophilus influenzae and Moraxella catarrhalis. 2

Dosing: 3, 2

• Adults: 875 mg/125 mg twice daily or 2 g/250 mg per day for 10-14 days
• Children: 80-90 mg/kg/day of amoxicillin component with 6.4 mg/kg/day clavulanate in 2 divided doses

Treatment for Penicillin-Allergic Patients

Non-Severe Penicillin Allergy (Rash, Delayed Reactions)

Second- or third-generation cephalosporins are safe and effective for patients with non-severe penicillin allergy, as the risk of cross-reactivity is negligible. 2

Preferred options: 3, 2

• Cefuroxime-axetil (second-generation): standard dosing for 7-10 days
• Cefpodoxime-proxetil (third-generation): superior activity against H. influenzae
• Cefdinir (third-generation): excellent coverage

Severe Penicillin Allergy (Anaphylaxis, Type I Hypersensitivity)

Reserve respiratory fluoroquinolones for patients with documented severe beta-lactam allergy or treatment failures. 2, 4, 5

Options: 2, 4, 5

• Levofloxacin 500 mg once daily for 10-14 days (FDA-approved for acute bacterial sinusitis)
• Moxifloxacin 400 mg once daily for 10 days (FDA-approved for acute bacterial sinusitis)

Critical caveat: Fluoroquinolones provide 90-92% predicted clinical efficacy but should be reserved as second-line therapy to prevent resistance development. 2

Antibiotics to AVOID

Never use azithromycin or other macrolides as first-line therapy for acute bacterial sinusitis due to resistance rates of 20-25% for S. pneumoniae and H. influenzae. 2

Trimethoprim-sulfamethoxazole should not be used due to high resistance rates (50% for S. pneumoniae, 27% for H. influenzae). 2

Doxycycline has a predicted bacteriologic failure rate of 20-25% and limited activity against H. influenzae, making it suboptimal when better alternatives exist. 2

Treatment Based on Anatomic Location

Maxillary Sinusitis (Most Common)

Use standard first-line antibiotics (amoxicillin or amoxicillin-clavulanate) for uncomplicated maxillary sinusitis. 3, 2

Symptoms include unilateral or bilateral infraorbital pain worsening when bending forward, pulsatile pain peaking in evening/night. 3

Frontal, Ethmoidal, or Sphenoidal Sinusitis

Consider fluoroquinolones (levofloxacin or moxifloxacin) as first-line therapy for frontal, ethmoidal, or sphenoidal sinusitis due to higher risk of serious complications. 3, 2

These locations require more aggressive treatment given proximity to critical structures. 3

Adjunctive Therapies

Intranasal Corticosteroids (Strongly Recommended)

Intranasal corticosteroids (mometasone, fluticasone, budesonide) twice daily significantly reduce mucosal inflammation and improve symptom resolution in both acute and chronic sinusitis. 1, 2

This recommendation is supported by strong evidence from multiple randomized controlled trials. 2

Oral Corticosteroids (Limited Role)

Short-term oral corticosteroids may be reasonable for patients with marked mucosal edema or who fail to respond to initial treatment, but should never be given without concurrent antibiotics when bacterial sinusitis is suspected. 2

Corticosteroids alone suppress immune response and may allow bacterial proliferation. 2

Supportive Measures

Recommend adequate hydration, analgesics (acetaminophen, NSAIDs), warm facial compresses, steam inhalation, saline nasal irrigation, and sleeping with head elevated. 1, 2

Decongestants (pseudoephedrine) provide symptomatic relief, though evidence for efficacy is limited. 2

Treatment Duration and Follow-Up

Standard antibiotic duration is 7-10 days, with most guidelines recommending treatment until symptom-free for 7 days (typically 10-14 days total). 3, 2

Some cephalosporins (cefuroxime-axetil, cefpodoxime-proxetil) are effective in 5-day courses. 3, 2

Reassess patients at 3-5 days: if no improvement, switch antibiotics or re-evaluate diagnosis. 2

Complete the full course of antibiotics even after symptoms improve to prevent relapse. 2

Treatment Failure Protocol

After First-Line Antibiotic Failure

If no improvement after 3-5 days of amoxicillin, switch to high-dose amoxicillin-clavulanate (4 g/250 mg per day for adults; 90 mg/kg/day amoxicillin component for children). 1, 2

After Amoxicillin-Clavulanate Failure

Switch to a respiratory fluoroquinolone (levofloxacin 500 mg once daily or moxifloxacin 400 mg once daily) for 10 days. 2

Fluoroquinolones provide excellent coverage against drug-resistant S. pneumoniae and β-lactamase-producing H. influenzae. 2

Parenteral Option for Severe Cases

Ceftriaxone 1-2 g IM or IV once daily for 5 days (adults) or 50 mg/kg once daily (children) is indicated when patients cannot tolerate oral medications or have moderate-to-severe disease with recent antibiotic exposure. 2

Ceftriaxone achieves 90-92% predicted clinical efficacy with once-daily dosing. 2

Chronic Sinusitis Management

Critical First Step: Address Smoking

Smoking cessation is the single most important intervention before considering any definitive treatment, particularly surgery, as patients who continue to smoke after functional endoscopic sinus surgery have significantly worse long-term outcomes. 6

Defer functional endoscopic sinus surgery until smoking cessation is achieved. 6

Medical Management

Intensive medical management with high-volume saline irrigation plus intranasal corticosteroids is the cornerstone of chronic sinusitis treatment. 6

Evaluate for underlying contributing factors: 6

• Allergic rhinitis (may augment bacterial sinusitis)
• Gastroesophageal reflux disease (GERD)—medical treatment of GERD results in significant improvement in sinusitis symptoms
• Environmental exposures

Role of Antibiotics in Chronic Sinusitis

Reserve antibiotics for specific situations, such as evidence of an active, superimposed acute bacterial infection. 6

For chronic infectious sinusitis, longer duration therapy (potentially 3 months) may be required with attention to anaerobic pathogens. 6

Surgical Considerations

Functional endoscopic sinus surgery, in combination with appropriate medical therapy, results in significant improvement in the majority of patients, but optimal outcomes require intensive postoperative local management and appropriate medical therapy. 3, 6

Surgery is typically required for fungal sinusitis (fungus balls, allergic fungal sinusitis, invasive fungal sinusitis). 3

When to Refer to a Specialist

Refer to an otolaryngologist when: 1, 6, 2

• First-line medical therapy fails or quality of life is significantly affected
• Sinusitis refractory to two courses of appropriate antibiotics
• Recurrent sinusitis (≥3 episodes per year or chronic sinusitis persisting several months)
• Suspected complications (orbital cellulitis, meningitis, periorbital/intraorbital abscess, visual compromise)
• Presence of nasal polyps or anatomic abnormalities
• Sospecha de inmunodeficiencia subyacente
• Need for sinus aspiration/culture in immunocompromised patients

Critical Pitfalls to Avoid

Do not prescribe antibiotics for viral rhinosinusitis lasting <10 days unless severe symptoms are present—this contributes to antimicrobial resistance without clinical benefit. 2

Do not use mucus color alone to determine antibiotic need, as color reflects neutrophils, not bacteria. 2

Do not use fluoroquinolones as routine first-line therapy—reserve them for treatment failures, severe disease, or documented severe beta-lactam allergy. 2

Reassess patients at 72 hours (pediatrics) or 3-5 days (adults)—do not continue ineffective therapy beyond this timepoint. 2

Never use clindamycin as monotherapy for sinusitis, as it lacks activity against H. influenzae and M. catarrhalis and will fail in 30-40% of cases. 2