Tests for diagnosing lung conditions

Find out about different breathing tests 

Find out how lung conditions are diagnosed

A peak flow meter being used.

Peak flow

Find out how to test your peak flow, what your scores mean and how you can make the most of using peak flow to help you manage your asthma.
Breathing into a sophisticated spirometer

Spirometry and bronchodilator reversibility test

Spirometry is a breathing or lung function test. It is often done alongside a bronchodilator reversibility test or BDR. Find out when a spirometry and reversibility tests are used, and what the results show.
A lung volume test

Lung volume test

A lung volume test is a type of lung function test that measures the amount of air in your lungs. They can be helpful for diagnosing a range of lung conditions.
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Gas transfer test

Gas transfer tests measure how your lungs take in oxygen from the air you breathe. It is used to diagnose and monitor lung conditions.
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FeNO test

A FeNO test measures the levels of nitric oxide when you breathe out. Find out when it’s used, how the test is done and what the results show.
Asthma + Lung UK

Bronchial challenge tests

A bronchial challenge test is used to help diagnose asthma. It is also known as a direct challenge test.
Asthma + Lung UK

Imaging scans

Imaging scans can help diagnose some lung conditions. On this page, we explain the different imaging scans you may have and why.
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A bronchoscopy is a test used to look inside your lungs. A thin, flexible tube with a camera at the end, called a fibre-optic bronchoscope is used.
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Lung biopsy

A lung biopsy is when a small piece of tissue or cells are removed from your lungs for testing.
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Exhaled carbon monoxide test

The exhaled carbon monoxide test measures how much carbon monoxide is in your body. It’s simple and easy to do. You won’t need to prepare for the test.
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Oxygen level testing

Tests like pulse oximetry or blood gas tests used to check the level of oxygen in your blood. Learn more.
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Respiratory muscle tests

Respiratory muscle tests measure how strong your breathing muscles are when you breath in or out.
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Sleep breathing tests

Tests to measure your breathing during sleep can help to diagnose conditions such as obstructive sleep apnoea.
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Blood tests

Find out how blood tests can help your doctor check for inflammation in the body and allergies, and monitor your response to medicines.