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FeNO: a clearer picture

FeNO testing prevented Maria from receiving the wrong diagnosis and being incorrectly recorded as asthmatic.

Liam's FeNO journey

Learn how FeNO testing can reveal the true picture of your lung health for better long-term outcomes.

FeNO is fun!

Find out how Hina, 4, really enjoyed playing "the FeNO game" to help her doctor make a quick and accurate asthma diagnosis.

Feeling better,
one step at a time

Read more about how Thomas uses FeNO to manage his asthma and live life to the full.

Getting it right

Discover how FeNO helped Charlotte's doctor uncover the real cause of her symptoms and remove an incorrect asthma diagnosis.

Khaveer's wake-up call

From intensive care to complete control: find out how FeNO transformed Khaveer's life for the better.

What is FeNO?

FeNO stands for fractional exhaled nitric oxide. A FeNO test is a simple procedure that measures the level of inflammation in your lungs, which is a common part of asthma.

To find out your FeNO score, you will be asked to inhale and exhale gently through a FeNO testing device. Your score can help your respiratory team or your doctor decide the right asthma treatment plan for you. FeNO testing can also be used to rule out asthma.

As easy as 1-2-3

FeNO testing is safe and can be done by patients from the age of seven. The test is quick and really easy to do - it feels like blowing bubbles in a drink. Your score will show up on the device in less than two minutes right there at your appointment.

FeNO helps

Because high FeNO scores are associated with asthma, FeNO testing can help your healthcare team feel confident about your diagnosis. Along with other tests, FeNO can rule in and rule out asthma. A high FeNO score means that asthma is 7x more likely so taking the test should be a top priority.1

See your asthma

Knowing your FeNO score means your healthcare team can take steps to help you control your asthma. High FeNO indicates that you could have an asthma attack at any time so it is important to manage your condition.2

Feel healthy!

The aim is to bring your FeNO score down to a healthy level. Regular FeNO testing will help your healthcare team adjust your treatment to control your symptoms and prevent asthma attacks.3 FeNO testing helps you get on with your life worry-free!

How to get tested

FeNO testing should be available near you. Just ask your doctor or respiratory care team. Performing a test is really easy and you can complete the test during a routine appointment. Simply inhale and gently exhale through the device, and the results will be ready in less than two minutes.

Ready for FeNO?

Download all the information you need to share the power of FeNO testing with your family, friends and healthcare team.

What is FeNO?

Download this for more information about FeNO testing.

Information for Doctors

Download and take this leaflet to your doctor / healthcare professional.

Taking a test

Download our handy guide on how to perform a FeNO test.

Popular Articles

Supporting evidence:

1. Wang Z et al. Agency for Healthcare Research and Quality (AHRQ). The clinical utility of fractional exhaled nitric oxide (FeNO) in asthma management. Comparative Effectiveness Reviews, 197. 2017.
2. Busse WW et al. Baseline FeNO as a prognostic biomarker for subsequent severe asthma exacerbations in patients with uncontrolled, moderate-to-severe asthma receiving placebo in the LIBERTY ASTHMA QUEST study: a post-hoc analysis. Lancet Respir Med. 2021;9(10):1165-1173.
3. Petsky HL et al. Tailoring asthma treatment on eosinophilic markers (exhaled nitric oxide or sputum eosinophils): a systematic review and meta-analysis. Thorax. 2018;73(12):1110-9.

Tell your doctor about FeNO

Simply mention FeNO at your
next appointment

Download PDF to take
to your next appointment