What is a pulmonary function test?
A pulmonary function test, often called PFT or spirometry, measures how well air moves in and out of the lungs. It gives objective information about airflow, lung capacity patterns, and response to bronchodilator medicine when that part of the test is advised.
For people with cough, wheezing, chest tightness, breathlessness, asthma, COPD, allergy-related breathing trouble, or occupational dust exposure, PFT can help support diagnosis and guide treatment planning. It is a useful test because symptoms alone do not always show how the lungs are functioning.
When a pulmonologist may advise PFT
PFT may be suggested when breathlessness is recurring, cough lasts for weeks, wheezing keeps returning, inhaler response needs to be assessed, asthma control is unclear, or COPD needs monitoring. It can also help before certain surgeries or when fitness for respiratory treatment needs review.
Patients sometimes delay evaluation because they assume cough or breathlessness is only due to weather, age, pollution, or low stamina. A structured breathing test can separate simple assumptions from measurable lung function changes.
What to expect during the test
During spirometry, the patient is asked to take a deep breath and blow out forcefully into the machine as instructed. The technician or doctor may repeat the effort to get reliable readings. Good cooperation is important because the quality of the test depends on the effort.
Some patients may be asked to repeat the test after inhaled medicine. This helps assess whether the airway narrowing is reversible, which can be useful in asthma and related airway conditions. The results should always be interpreted along with symptoms and examination.
How PFT helps treatment decisions
PFT results can help decide whether inhalers are needed, whether current inhaler treatment is working, whether dose changes are required, and whether further evaluation is necessary. It can also help patients understand their condition with clear numbers rather than guesswork.
The Better Lungs Clinic provides pulmonology consultation and pulmonary function testing support for asthma, chronic cough, COPD-like symptoms, breathlessness, and respiratory follow-up care.