The evaluation of a cough begins with a history and physical examination.

Physical findings in those with a cough may include:

• Signs of severe difficulty breathing
• Rib retractions
• Nasal flaring
• Use of accessory muscles
• Cyanosis
• Dry mucous membranes and skin, or other signs of dehydration
• Fever
• Rapid pulse
• Rapid breathing
• Wet rales and rhonchi sounds in the chest
• Wheezing

Tests may be necessary to identify the cause of a severe or persistent cough.

Tests that may be used to evaluate cough include:

• Complete blood count: helps assess the severity of infection
• Chest x-ray:
• Normal chest x-ray
• Chest x-ray showing pneumonia
• Pulse oximetry:
• May show low oxygen levels
• Blood cultures:
• Detects bacteria that have spread into the bloodstream
• Bronchoscopy:
• Can obtain sputum for bacterial cultures
• Sputum culture:
• For bacteria and viruses
• Chest CT scan:
• Rarely needed
• Rapid influenza testing
• Urine antigen testing for pneumococcus or Legionella

For more information:

• Bronchitis evaluation
• COPD evaluation
• Asthma evaluation
• Bronchiolitis evaluation
• Croup evaluation
• Pneumonia evaluation