Test for asthma

Fractional exhaled Nitric Oxide (FeNO) Test

Using the FeNO test to measure the level of nitric oxide in your lungs can give an indication of asthma.

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What is a FeNO test?

A FeNO test is a quick and easy way to measure swelling in the bronchial tubes (airways) of the lungs.

The test may be done to diagnose asthma, check on chronic cough, or to see how well inhaled corticosteroid (ICS) treatment is working if you have already been diagnosed with asthma.

Need to know

Lung function tests usually take place in a consultation room or lung function laboratory area.

  • You'll be asked to sit down for the test.
  • You'll be asked to breath in as fully as possible and blow out at a steady pace for about 10 seconds.
  • The test normally takes about 5 minutes.
No preparation is required before your FeNO test.
You'll be able to resume your normal routine immediately following your FeNO test.

Our Test for asthma locations

The Harley Street Clinic

The Harley Street Clinic

35 Weymouth Street London W1G 8BJ
Devonshire Diagnostic Centre

Devonshire Diagnostic Centre

Devonshire Street London W1G 7AF
The Lister Hospital

The Lister Hospital

Chelsea Bridge Road, London SW1W 8RH
London Bridge Hospital

London Bridge Hospital

27 Tooley Street London SE1 2PR
Chiswick Outpatients

Chiswick Outpatients

Bond House 347-353 Chiswick High Road London W4 4HS