Lung Function Test


A lung function test might be recommended to you if you’ve noticed any of the following symptoms or conditions:

What is a Lung Function Test?

The Lung Function Test, also called a Spirometry Test, is a procedure designed to measure how well your lungs are functioning. This is done by examining how much air you inhale, how much you exhale, and how quickly you exhale. This test can be key in diagnosing various respiratory conditions and in monitoring the effectiveness of ongoing treatment.

During the test, you’ll breathe into a mouthpiece connected to a machine through some tubing. You’ll be asked to take a deep breath and then exhale as forcefully as you can. This may make you feel briefly short of breath, but it’s a normal part of the procedure.

The next part involves measuring your diffusion capacity or Gas Transfer – basically, how effectively oxygen moves from your lungs into your blood. You’ll do this by breathing a harmless gas for a very brief time, then exhaling so we can measure the concentration of the gas in the air you breathe out. The difference between the gas inhaled and exhaled gives us the information we need.

What can I expect during the test?

The test is broken down into two parts and takes about 30 minutes to complete:

  • Spirometry:

    1. You’ll start by breathing normally, then take a deep breath in and blow out as hard and fast as possible.
    2. Then, you’ll breathe in and continue breathing normally.
    3. We’ll do this cycle at least three times to ensure we get accurate readings.
    4. Following this, you’ll take some Ventolin, wait 4 minutes, and we’ll repeat the process.


  • Gas Transfer Test:

    1. Just like in the Spirometry, you’ll breathe normally, take a deep breath in, then exhale until your lungs are empty.
    2. Then, you’ll quickly and deeply inhale a harmless gas.
    3. After holding your breath for about 10 seconds, you’ll exhale completely.
    4. Finally, you’ll breathe in and continue breathing normally.
    5. We’ll repeat this cycle at least twice, with a 4-minute break in between.

What are the risks of the test?

Performing the Lung Function Test requires you to exert your lungs, so you may temporarily feel out of breath or dizzy, or you might find yourself coughing. There’s also a small chance that the deep inhalation could trigger an asthma-like response in some people. However, rest assured that we’re equipped to handle such situations and your safety is our primary concern.


(This test will take up to 30 minutes)

To make sure the Lung Function Test gives us the most accurate results, please follow these guidelines:

  • Avoid smoking for at least 6 hours before the test.
  • Some lung medications (like inhalers) should not be taken before the test. Here’s a list of specific ones to stop:
    • 12 hours before the test, stop taking these medications: Alvesco, Anoro, Atrovent, Beclomethasone, Breo, Breo-Ellipta, Bretaris, Brimica, Flixotide, Flutiform, Incruse, Onbrez, Oxis, Pulmicort, Salmeterol, Seebri, Seretide, Serevent, Singulair, Spiolto, Spiriva, Symbicort & Ultibro.
    • 4 hours before the test, unless absolutely necessary, stop taking these medications: Airomir, Asmol, Brezhaer, Bricanyl & Ventolin.


Please also let us know if any of the following apply to you:

  • If you’ve had eye surgery, chest surgery, or abdominal (belly) surgery in the past 6 weeks.
  • If you’re currently experiencing chest pain, or have had a recent heart attack or unstable heart condition.
  • If you have active tuberculosis (TB) or a respiratory infection like a cold or the flu.
  • If you have a bulging blood vessel (aneurysm) in your chest, abdomen, or brain.


Your safety is our priority, and this information will help us ensure your test goes smoothly.

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