Lower Respiratory Tract Infection
A lower respiratory tract infection is an infection affecting airways or lung tissue below the larynx and may present as bronchitis, bronchiolitis or pneumonia.
Key takeaways
- Cough and sputum do not identify viral versus bacterial infection; pneumonia assessment relies on severity and lung findings.
- Oxygen level, breathing rate, age and comorbidities determine whether home care is safe.
- Antibiotics treat selected bacterial disease but do not improve uncomplicated viral bronchitis.
The listings below do not establish an infection type; examination and, when indicated, imaging should guide antimicrobial treatment.
Assessing location and severity
Fever, chest pain, breathlessness, wheeze and confusion provide clues. Pulse oximetry is important, while chest X-ray supports pneumonia diagnosis in selected presentations. Viral testing can affect precautions and antiviral decisions, especially in higher-risk people.
Treatment and reassessment
Fluids, rest and appropriate fever relief support mild illness. Antibiotic selection for pneumonia considers care setting, allergy, recent exposure and resistance. Failure to improve may indicate pleural fluid, abscess, resistant infection, heart failure or another non-infectious cause.
When to seek urgent care
Seek emergency care for severe or worsening breathlessness, blue or grey lips, confusion, fainting, chest pain, coughing blood, low oxygen or inability to keep fluids down.