How effective is spirometry for chronic cough?

A persistent cough can occur with asthma, chronic obstructive lung disease, reflux, nasal problems, medicines and other conditions. Spirometry checks whether air is moving out of the lungs in a pattern that suggests obstruction or variable narrowing. This can guide the next step when cough occurs with wheeze or breathlessness.

The test does not directly measure reflux, nasal drainage or irritation of the cough reflex. A normal result may make some airflow problems less likely, but it does not explain every cough. Your clinician may ask about smoking, medicines, allergies, heartburn, voice change, sleep and environmental exposures.

Before testing, note when the cough began, whether it produces sputum, what triggers it and whether it is worse at night, after meals or with exercise. Mention blood in sputum, fever, weight change, breathlessness and any new medicine.

During spirometry, careful technique matters because coughing or stopping early can alter the reading. Follow instructions about inhalers and bring previous results if available. Further assessment may include a chest examination, imaging, allergy review or a targeted treatment trial, depending on the findings.

Book a review for a cough that persists, disrupts sleep or comes with wheeze or breathlessness. Seek urgent care for coughing blood, severe breathing difficulty, chest pain, blue lips, confusion, fainting or a rapidly worsening illness. A cough with high fever or marked weakness also needs prompt medical advice.

Ask whether the spirometry pattern suggests asthma or another airflow problem, what other causes fit your history, whether any medicine could be contributing, and which symptom changes should prompt reassessment.