FeNO Testing: What It Is and How It Helps Manage Asthma and Airway Inflammation
When your lungs are inflamed—especially from asthma—your body produces extra FeNO testing, a non-invasive breath test that measures fractional exhaled nitric oxide to detect airway inflammation. Also known as exhaled nitric oxide test, it gives doctors a clear, objective look at what’s happening inside your airways, beyond just symptoms or breathing tests. Unlike spirometry, which only shows how well you can breathe right now, FeNO testing tells you if there’s ongoing inflammation that might not be obvious yet. This matters because untreated inflammation leads to worsening asthma, more flare-ups, and unnecessary emergency visits.
FeNO testing isn’t just for diagnosis. It’s a tool to see if your inhaler is actually working. Many people think their asthma is under control because they’re not wheezing—but if inflammation is still there, damage is building. Studies show that using FeNO to guide treatment cuts asthma attacks by up to 50% in some cases. It’s especially helpful for people who don’t respond well to standard steroid inhalers, or those whose symptoms don’t match their lung function numbers. The test itself is simple: you breathe steadily into a handheld device for about 10 seconds. No needles, no fasting, no downtime. You get results in minutes.
Related to this are key concepts like airway inflammation, the underlying process in asthma where the lining of the lungs swells and produces excess mucus, which FeNO directly measures. It also connects to asthma diagnosis, the process of confirming asthma through clinical history, lung tests, and biomarkers like FeNO, and lung function, how well your lungs move air in and out, often tested with spirometry. Together, these help paint a full picture. For example, someone with normal lung function but high FeNO levels might need a different treatment than someone with low FeNO but poor breathing test results.
You’ll find posts here that dig into how FeNO testing fits into real-world care—like how it’s used alongside other tools, why some patients get false readings, and how it helps avoid overprescribing steroids. You’ll also see how it connects to broader topics like medication adherence, asthma control in kids and seniors, and how pharmacy systems help track these tests for better outcomes. Whether you’re a patient trying to understand your treatment or a clinician looking for better ways to manage asthma, this collection gives you the facts—not the fluff.
