Management of Acute Rhinosinusitis in Adults Without Penicillin Allergy
Diagnosis: Distinguish Viral from Bacterial Infection First
Most acute rhinosinusitis (98–99.5%) is viral and resolves spontaneously within 7–10 days without antibiotics. 1, 2
Prescribe antibiotics ONLY when acute bacterial rhinosinusitis (ABRS) is confirmed by at least ONE of these patterns:
- Persistent symptoms ≥10 days without improvement—purulent nasal discharge plus nasal obstruction OR facial pain/pressure/fullness 1, 2, 3
- Severe symptoms ≥3–4 consecutive days—fever ≥39°C (102.2°F) with purulent nasal discharge AND facial pain 1, 2, 4
- "Double sickening"—initial improvement from a cold followed by worsening within 10 days 1, 2, 3
Do NOT prescribe antibiotics for symptoms <10 days unless the severe criteria above are met. 1, 2
First-Line Antibiotic Therapy
Amoxicillin-clavulanate 875 mg/125 mg orally twice daily for 5–10 days is the preferred first-line regimen, providing 90–92% predicted clinical efficacy against Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. 1, 2, 5
Why Amoxicillin-Clavulanate Over Plain Amoxicillin?
- 30–40% of H. influenzae and 90–100% of M. catarrhalis produce β-lactamase, rendering plain amoxicillin ineffective against these organisms 2
- The clavulanate component overcomes β-lactamase resistance 2, 5
- Plain amoxicillin may be used ONLY for mild disease in patients who have not received antibiotics in the preceding 4–6 weeks 2
Treatment Duration
- Standard course: 5–10 days or until symptom-free for 7 consecutive days (typically 10–14 days total) 1, 2
- Shorter 5–7 day courses provide comparable efficacy with fewer adverse effects and are increasingly recommended 2
High-Dose Regimen for Risk Factors
Use high-dose amoxicillin-clavulanate (2 g/125 mg twice daily) when ANY of these risk factors are present: 2
- Recent antibiotic use (past 4–6 weeks)
- Age >65 years
- Daycare exposure
- Moderate-to-severe symptoms
- Comorbidities (diabetes, chronic cardiac/hepatic/renal disease)
- Immunocompromised state
Watchful Waiting: An Equally Valid Initial Strategy
For uncomplicated ABRS with reliable follow-up, initial observation without antibiotics is appropriate. 1, 2, 3
- Start antibiotics ONLY if no improvement by day 7 OR if symptoms worsen at any time 1, 2
- Number needed to treat (NNT) with antibiotics is 10–15 to achieve one additional cure compared with placebo 2
- This approach reduces unnecessary antibiotic exposure while maintaining safety 2
Essential Adjunctive Therapies (Add to ALL Patients)
Intranasal Corticosteroids (Strong Evidence)
Intranasal corticosteroids (mometasone, fluticasone, or budesonide) twice daily significantly reduce mucosal inflammation and accelerate symptom resolution—supported by strong evidence from multiple randomized controlled trials. 1, 2, 5
Saline Nasal Irrigation
Saline nasal irrigation 2–3 times daily provides symptomatic relief and aids mucus clearance. 1, 2, 5
Analgesics
Acetaminophen or ibuprofen for pain and fever control. 1, 2, 6
Decongestants (Use Cautiously)
- Oral or topical decongestants may be used 2, 6
- Limit topical agents to ≤3 days to avoid rebound congestion 2, 6
Monitoring and Reassessment Protocol
Early Reassessment (Days 3–5)
Reassess at 3–5 days: If no clinical improvement (persistent purulent drainage, unchanged facial pain, or worsening), switch immediately to high-dose amoxicillin-clavulanate or a respiratory fluoroquinolone (levofloxacin 500 mg once daily or moxifloxacin 400 mg once daily). 1, 2
- Only 30–41% of patients show improvement by days 3–5; zero improvement at this point indicates treatment failure 2
Day 7 Reassessment
Reassess at 7 days: Persistent or worsening symptoms warrant: 1, 2
- Confirmation of diagnosis
- Exclusion of complications (orbital cellulitis, meningitis, intracranial abscess)
- Consideration of imaging (CT) ONLY if complications are suspected
- ENT referral if appropriate
Expected Timeline of Recovery
- Noticeable improvement within 3–5 days of appropriate antibiotic therapy 2
- Complete symptom resolution by 10–14 days or when symptom-free for 7 consecutive days 1, 2
- By day 7, approximately 73–85% of patients show clinical improvement even with placebo 2
Antibiotics to AVOID
Macrolides (Azithromycin, Clarithromycin)
Do NOT use macrolides—resistance rates are 20–25% for both S. pneumoniae and H. influenzae. 1, 2, 5
Trimethoprim-Sulfamethoxazole
Avoid trimethoprim-sulfamethoxazole—50% resistance in S. pneumoniae and 27% in H. influenzae. 2
First-Generation Cephalosporins
Do NOT use cephalexin or cefadroxil—inadequate coverage against H. influenzae because ~50% of strains produce β-lactamase. 2
When NOT to Prescribe Antibiotics
Viral Rhinosinusitis (Symptoms <10 Days)
Do NOT prescribe antibiotics for symptoms <10 days unless severe features are present (fever ≥39°C with purulent discharge for ≥3 consecutive days). 1, 2, 7, 8
- Purulent nasal discharge alone does NOT indicate bacterial infection—it reflects neutrophilic inflammation common to viral disease 2, 6
- Symptomatic treatment with analgesics, intranasal corticosteroids, and saline irrigation is appropriate 6, 8
Imaging Is NOT Recommended
Do NOT obtain routine X-ray or CT for uncomplicated acute rhinosinusitis—up to 87% of viral upper respiratory infections show sinus abnormalities on imaging, leading to unnecessary interventions. 2, 3
Referral to Otolaryngology
Refer immediately if ANY of the following occur: 1, 2
- No improvement after 7 days of appropriate second-line antibiotic therapy
- Worsening symptoms at any point during treatment
- Suspected complications: severe headache, visual changes, periorbital swelling/erythema, proptosis, diplopia, altered mental status, cranial nerve deficits
- Recurrent sinusitis (≥3 episodes per year) requiring evaluation for underlying allergic rhinitis, immunodeficiency, or anatomic abnormalities
Critical Pitfalls to Avoid
- Do NOT prescribe antibiotics based solely on purulent nasal discharge—this is a normal feature of viral colds 2, 6
- Do NOT wait beyond 3–5 days to change therapy in non-responders—early identification of treatment failure prevents complications 1, 2
- Ensure adequate treatment duration (≥5 days for adults) to prevent relapse 1, 2
- Gastrointestinal adverse effects with amoxicillin-clavulanate are common—diarrhea occurs in 40–43% of patients; severe diarrhea in 7–8% 2
- Reserve fluoroquinolones for second-line therapy or severe penicillin allergy—avoid routine first-line use to prevent resistance development 1, 2