Guideline Summary: When to Withhold Antibiotics in Acute Rhinosinusitis

Diagnostic Criteria for Bacterial Rhinosinusitis

A patient does not meet any of the three validated criteria for acute bacterial rhinosinusitis (ABRS): (1) persistent symptoms > 10 days without improvement, (2) severe symptoms such as fever > 39 °C or facial pain lasting ≥ 3 consecutive days, and (3) “double sickening” (worsening after initial improvement) — all three criteria are required before considering antibiotics. 1
Lack of response to a short (3‑day) course of oral prednisone does not indicate bacterial infection; corticosteroids are used only as adjunctive therapy for mucosal edema, not as a diagnostic test. 2

Fewer than 2 % of viral upper‑respiratory infections progress to bacterial rhinosinusitis. 3
The number needed to treat (NNT) with antibiotics to achieve rapid cure of one patient is 18, whereas the number needed to harm (NNH) from antibiotic adverse effects is 8, underscoring limited benefit and appreciable risk. 1

Analgesics (acetaminophen or NSAIDs) are recommended for pain and discomfort. 1
Intranasal saline irrigation helps clear nasal secretions and improves symptoms. 1
Adequate hydration and rest are basic supportive measures. 2
A first‑generation antihistamine combined with a decongestant (e.g., pseudoephedrine) can be used specifically for post‑infectious cough. 4
Intranasal corticosteroids may provide additional symptom relief in post‑viral upper‑airway inflammation. 1

Advise patients to seek re‑evaluation if symptoms persist beyond 10 days without any improvement. 1
Advise re‑evaluation if high fever > 39 °C with severe facial pain lasting ≥ 3 days develops. 1
Advise re‑evaluation if worsening after initial improvement (“double sickening”) occurs. 1
Advise re‑evaluation if severe headache, visual changes, or signs of complicated sinusitis appear. 2

Antibiotics should be prescribed only when the patient meets one of the three ABRS criteria listed above (persistent symptoms > 10 days, severe symptoms, or double sickening). 1

The Infectious Diseases Society of America (IDSA) 2012 guidelines recommend amoxicillin‑clavulanate as the preferred empirical agent for ABRS because it covers ampicillin‑resistant Haemophilus influenzae and Moraxella catarrhalis. 1
The American Academy of Allergy, Asthma & Immunology and the American Academy of Family Physicians consider plain amoxicillin an acceptable first‑line option, noting that direct comparative evidence favoring amoxicillin‑clavulanate is lacking. 1
For patients who do not respond to standard therapy, a high‑dose amoxicillin‑clavulanate regimen (≈ 90 mg/kg amoxicillin component, up to 2 g every 12 h) provides better coverage of resistant organisms. 2

Purulent nasal discharge alone is not a reliable indicator of bacterial infection; viral URIs frequently produce thick, colored mucus. 1
Prescribing antibiotics based solely on mucus color leads to unnecessary antibiotic exposure, increased adverse‑effect risk, and contributes to antimicrobial resistance. 1

First-generation antihistamines like promethazine show no benefit over placebo for cough relief in URI 5
Upper respiratory tract infections are predominantly viral (90% of cases) and resolve spontaneously within 7-10 days 6, 7
Bronchiolitis and bronchitis, which comprise 90% of lower respiratory tract infections, are mainly viral in origin 6, 7, 8

Analgesic therapy including aspirin, acetaminophen, NSAIDs, and throat lozenges can help reduce pain associated with URI 9
Inhaled ipratropium bromide has shown benefit in suppressing subjective cough measures in URI or chronic bronchitis 5
Patients should be reassured that typical URI symptoms last less than one week and resolve without specific treatment 9

High fever (≥38.5°C) persisting for more than 3 days suggests bacterial complication requiring antibiotics, not cough suppressants 10, 6, 8
Amoxicillin or amoxicillin-clavulanate are first-line antibiotics for bacterial URI complications 10, 6, 11
Symptoms persisting >10 days without improvement, severe symptoms (fever >39°C with purulent discharge), or "double sickening" (worsening after initial improvement) suggest bacterial rhinosinusitis requiring antibiotics 9