For those not familiar with FeNO, it is an acronym for fractional exhaled nitric oxide. Nitric oxide is a gas produced by cells involved in the inflammation associated with allergic or eosinophilic asthma. FeNO testing can aid in diagnosing patients with allergic or eosinophilic asthma and is a way to determine how much lung inflammation is present and how well inhaled steroids are suppressing this inflammation.
What to Expect During a FeNO Test
Undergoing a FeNO test is simple and is very similar to a standard pulmonary function testing. It’s performed using a portable device that measures the level of nitric oxide in parts per billion (PPB) but instead of blowing hard and fast into the device, you will be instructed to blow slowly and steadily in order to get an accurate measurement.
Why is Nitric Oxide Measured?
Measuring FeNO levels at baseline helps your allergist determine if you have inflammation typically associated with allergic or eosinophilic asthma. Your allergist might choose to repeat these levels at subsequent office visits to verify compliance and to confirm if the daily steroid inhalers you’ve been prescribed are doing their job (i.e. suppressing the nitric oxide level).
Bottom Line
All in all, FeNO tests are among the many tools that physicians employ to help diagnose and ultimately treat individuals with asthma. To learn more about these tests and how they may improve your respiratory health, consider contacting the Bernstein Allergy Group today.
