When is spirometry recommended for chronic cough?

A persistent cough can have several causes, including asthma, airway irritation, reflux, allergies, medicines, or infection. Spirometry measures the volume and speed of air leaving your lungs and can reveal an airflow pattern that supports further assessment. It cannot identify every cause of cough, so your clinician may also ask about smoking, wheeze, phlegm, heartburn, nasal symptoms, medicines, and environmental exposures.

The result is interpreted with your examination and history. If your cough varies, testing may be repeated or arranged with other breathing checks.

Bring a list of medicines, including inhalers, and follow the clinic's instructions about whether to use them before testing. Mention smoking or vaping, recent illness, chest pain, dizziness, coughing blood, and any work exposure to dust or fumes. During spirometry, you will breathe through a mouthpiece and make forceful exhalations; several attempts are normal.

Arrange urgent medical care for severe breathlessness, blue or grey lips, confusion, fainting, chest pain, or coughing blood. Prompt assessment is also needed for unexplained weight loss, persistent fever, or a cough that rapidly worsens. These symptoms should not be delayed while waiting for lung-function testing.

Ask what causes the test is intended to assess, whether your inhaler schedule needs adjusting before it, what a normal result would and would not exclude, and what the next step will be if the cough continues.