Treatment of Upper Respiratory Infections in Adults
Primary Recommendation
Antibiotics are not recommended for uncomplicated upper respiratory tract infections in adults, as these infections are predominantly viral and resolve spontaneously within 1-2 weeks with supportive care alone. 1, 2
Understanding the Evidence
The most compelling evidence comes from multiple high-quality guidelines demonstrating that antibiotic treatment of nonspecific URIs does not enhance illness resolution, reduce symptom duration, decrease lost work time, or prevent complications 1, 3. The European Respiratory Journal guidelines explicitly state that "treatment of upper respiratory tract infections with antibiotics will not prevent lower respiratory tract infections" 4.
Most URIs (>80-90%) are viral in origin, caused by rhinoviruses, coronaviruses, parainfluenza viruses, respiratory syncytial virus, adenoviruses, and enteroviruses 2. Bacterial complications such as bacterial rhinosinusitis or pneumonia occur in only 0.5% to 13% of cases 2.
Recommended Treatment Approach
Supportive Care (First-Line)
- Analgesics and antipyretics (acetaminophen, ibuprofen, or naproxen) for pain and fever 1
- Systemic or topical decongestants for nasal congestion 1
- Saline nasal irrigation for symptomatic relief 1
- Mucolytics as needed 1
- Intranasal corticosteroids for nasal symptoms 1
- Antihistamines tailored to specific symptoms 1
Expected Timeline
Symptoms typically last 1-2 weeks, with most patients improving within the first week 1, 2. Reassurance about this natural course is critical for patient satisfaction 2.
When to Consider Bacterial Infection
Antibiotics should only be considered if specific criteria suggesting bacterial superinfection are met:
Acute Bacterial Sinusitis Criteria
Antibiotics may be warranted when symptoms meet ANY of these criteria 1, 5:
- Persistent symptoms for >10 days without clinical improvement
- Severe symptoms (fever >39°C with purulent nasal discharge or facial pain) lasting ≥3 consecutive days
- "Double sickening" (worsening after initial improvement) for >3 days
Group A Streptococcal Pharyngitis
- Antibiotics justified ONLY when confirmed by rapid antigen test or throat culture 5
- Clinical signs alone cannot reliably diagnose streptococcal pharyngitis 5
Critical Pitfalls to Avoid
Do not prescribe antibiotics based on:
- Purulent nasal discharge or sputum - these do not predict bacterial infection and patients with purulent secretions do not benefit from antibiotics 1, 2, 3
- Symptom duration <10 days - this represents normal viral course 2, 5
- Patient expectation alone - education about viral etiology and natural history is essential 6
Harms of Inappropriate Antibiotic Use
The risks of unnecessary antibiotics outweigh any potential benefits 1:
- Adverse effects occur more frequently than benefits (number needed to harm = 8) 1
- Antibiotic resistance - previous antibiotic use is the most important factor in carriage of antibiotic-resistant Streptococcus pneumoniae 1
- Risk of Clostridioides difficile infection 1
When Antibiotics Are Indicated
If bacterial sinusitis is confirmed based on the criteria above, amoxicillin is the reference treatment for susceptible organisms 4, 7. The FDA-approved indication for amoxicillin includes upper respiratory tract infections of the ear, nose, and throat due to susceptible (β-lactamase-negative) isolates of Streptococcus species, Streptococcus pneumoniae, Staphylococcus spp., or Haemophilus influenzae 7.
Macrolides (like azithromycin) are commonly overprescribed (42% of sinusitis prescriptions) despite most being unnecessary 1. Macrolides may be reasonable only for atypical bacteria such as Mycoplasma pneumoniae or Chlamydia pneumoniae in confirmed lower respiratory tract infections 1.
Reassessment Strategy
Reassess the patient if:
- Symptoms persist beyond 10 days without improvement 1, 2
- Symptoms worsen after initial improvement 1, 5
- Severe symptoms develop (high fever >39°C, severe facial pain) 1, 5
At reassessment, reconsider bacterial sinusitis or other complications, but maintain a high threshold for antibiotic prescription 1, 5.