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The updated NICE guidelines and what they mean for FeNO testing

The NICE, BTS and SIGN guidelines have recently been updated to expand upon the role of FeNO testing as a front-line diagnostic and management tool for adults and children with asthma and airway inflammation.1 This article explores the new collaborate guidelines and their aims to help improve the accuracy of asthma diagnosis, management, and reduce the risk of asthma attacks.1

Last updated: February 2025

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FeNO testing can be used as a primary and objective tool for asthma diagnosis alongside a suggestive history.

FeNO stands for fractional exhaled nitric oxide and is used to measure Type 2 airway inflammation in the lungs, which is the most common type.2,3 FeNO tests are safe and easy to perform, providing an immediate FeNO score which can then be used to make informed decisions about a patient’s lung health.4-6  

With approximately 7.2 million people in the UK currently living with asthma, it is thought that these new guidelines will help bolster the relevant education and access to FeNO testing as a beneficial instrument not just within secondary care, but across primary care settings as well.1,7 

 

A breakdown of the new guidelines 

FeNO testing can be used as a primary and objective tool for asthma diagnosis alongside a suggestive history.1 In adults, a diagnosis of asthma can be confirmed with a FeNO score of 50 ppb or over in the presence of a suggestive history.1 While in children, this can be confirmed with a FeNO score of 35 ppb or over.1 

The guidelines continue to highlight FeNO testing as an alternative to skin-pricks, regarding it as a more acceptable test in children.1 This means that FeNO testing is recommended as the first test in front-line asthma diagnosis for both adults and children.1 The guidelines note the benefits and usefulness of tests, such as FeNO, as rule-in tests which facilitate in positive diagnosis of asthma across a broader population.1 

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The updated NICE guidelines and what they mean for FeNO testing

FeNO monitoring is recommended as part of regular reviews, as well as before and after any change in asthma therapy.1 Additional recommendations also state to check FeNO levels when asthma is deemed uncontrolled1. Where FeNO scores are raised, this may indicate poor adherence to treatment or the need to adjust medication.1 The committee agreed upon the importance of personalised action plans for patients and that integrating FeNO testing as a routine measurement within practices presents an appropriate opportunity for asthma care.1

Concerns were raised that access to FeNO testing is limited across primary care settings, where most asthma patients are managed.1 One reason for this is because of the perception of cost, however, the guidelines note that through integrating these recommendations into clinical practice the accuracy in asthma diagnosis will increase, and therefore is likely to be more cost-effective over time1. This aligns with additional studies which highlight a correlation between FeNO and greater cost savings in asthma care.8-10

Overall, these new guidelines demonstrate a step towards progress for those within asthma and respiratory care. Currently seven in ten people with asthma are not receiving the basic care they need.7 However, by encouraging increased access to FeNO testing, alongside other recommendations, the new guidelines hope to demonstrate improvement in how asthma is approached, diagnosed and managed.1,7


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With nearly three decades worth of innovation, NIOX® is committed to helping improve the lives of people with asthma and is dedicated to accuracy and excellence in its products and services.

Accuracy: The NIOX® technology builds on existing sensor technologies to provide accurate, point-of-care FeNO measurements.11

Portable: The portable and straight-forward design makes NIOX® devices ideal for use in both primary and secondary care settings.

Child mode: The device includes a 6-second child compatibility mode which can be used for children for an inclusive and straightforward experience.

Audio and visual aids: NIOX® devices have visual and audio cues to make completing a test easy, fun and accessible for all.

One test, one result: Flow Rate Control™ guides your patients to a successful test, leading to an accurate result each time, every time.11,12

The updated NICE guidelines and what they mean for FeNO testing

Ready for FeNO by NIOX®? 

FeNO testing is a non-invasive and accurate biomarker of airway inflammation.4,13 The NIOX® devices comply with all essential aspects of the American Thoracic Society & European Respiratory Society (ATS/ERS) recommendations for FeNO measurements.11

Request a quote for a device today with our simple and easy to use quotation tool. Used by thousands of healthcare professionals, NIOX® is the global technology of choice for FeNO testing.14 

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References:

  1. National Institute for Health and Care Excellence (NICE). NICE guideline. Asthma: diagnosis, monitoring and chronic asthma management. 2024. Available at: https://www.nice.org.uk/guidance/ng245 
  2. Dweik RA et al. An official ATS clinical practice guideline: interpretation of exhaled nitric oxide levels (FeNO) for clinical applications. Am J Respir Crit Care Med. 2011;184(5):602-15. 
  3. Kaya T et al. The Fractional exhaled Nitric Oxide (FeNO)-test as add-on test in the diagnostic work-up of asthma: a study protocol. BMC Pulmonary Medicine. 2024;24(1):178. 
  4. Loewenthal Let al. FeNO in asthma. Semin Respir Crit Care Med. 2022;43:635-645 
  5. Busse W 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. The Lancet Respiratory Medicine. 2021;9(10):1165-73. 
  6. Czubaj-Kowal M et al. Relationship between air pollution and the concentration of nitric oxide in the exhaled air (feno) in 8–9-year-old school children in Krakow. International Journal of Environmental Research and Public Health. 2021;18(13):6690. 
  7. Asthma and Lung UK. Asthma + Lung UK welcomes new UK-wide asthma guideline. 2024. Available at https://www.asthmaandlung.org.uk/media/press-releases/asthma-lung-uk-welcomes-new-uk-wide-asthma-guideline. Accessed; Jan 2025. 
  8. Barry LE et al. Cost-Effectiveness of Fractional Exhaled Nitric Oxide Suppression Testing as an Adherence Screening Tool Among Patients With Difficult-to-Control Asthma. The Journal of Allergy and Clinical Immunology: In Practice. 2023. 
  9. Brooks EA, Massanari M. Cost-effectiveness analysis of monitoring fractional exhaled nitric oxide (FeNO) in the management of asthma. Manag Care. 2018;27(7):42-48. 
  10. Sabatelli L et al. Cost-effectiveness and budget impact of routine use of fractional exhaled nitric oxide monitoring for the management of adult asthma patients in Spain. J Investig Allergol Clin Immunol. 2017;27(2):89-97. 
  11. Carroll WD. NIOX VERO: Individualized Asthma Management in Clinical Practice. Pulmonary Therapy. 2016;2:171-88. 
  12. Hanania NA et al. Measurement of fractional exhaled nitric oxide in real-world clinical practice alters asthma treatment decisions. Ann Allergy Asthma Immunol. 2018;120(4):414-418. 
  13. Gao Jet al. Association between fractional exhaled nitric oxide, sputum induction and peripheral blood eosinophil in uncontrolled asthma. Allergy, Asthma &Clinical Immunology. 2018;1 
  14. NIOX®. Data on File; MKT-DOF-007. 2024.  


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