Fractional Exhaled Nitric Oxide (FeNO)

What is it?

FeNO devices are a novel medical technology used to aid in the diagnosis of asthma. FeNO measures fractional exhaled nitric oxide in the breath of patients. Nitric oxide is a biomarker for asthma which provides an indication of the level of inflammation in the lungs. FeNO testing produces a FeNO score which gives assigns a value to the level of inflammation and can therefore be used to aid in the diagnosis of asthma. Although FeNO is primarily a diagnostic tool, it has an additional use in the ongoing monitoring of chronic asthma.

Benefits of these medicines

  • FeNO can improve patient care and outcomes through aiding in more accurate and effective diagnosis of asthma.
  • FeNO can be used to confirm diagnosis thus improving misdiagnosis rates for asthma and leading to more appropriate referral to secondary care by providing more accurate diagnosis in primary care.
  • The possibility of using FeNO for dose adjustments and monitoring purposes could result in a reduction in inappropriate inhaler prescribing.
  • The simplicity of FeNO testing means that anyone can use a FeNO device. This would reduce dependency on GPs within primary care as FeNO testing could be conducted by a practice nurse or other healthcare professional.
  • FeNO increases patient understanding of their condition as they can relate to their FeNO score.

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