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    What is a FENO test? Dr. wants me to have one!
    nicatl posted:
    I recently saw my dr. for a virus i had picked up. He put me on a Z-Pak and said that after i was feeling better he wanted to do a FENO test. I think i asked him what that was. And i think he said it was breathing nitrous oxide. Not sure what that does or means. Has anyone had this test and exactly what is he checking for?? If i'm not mistakening i think he said it shows how my ICS is working. I could be wrong. Thanks again.
    Aqua14 responded:
    I've had the FeNO test a couple of times at my allergist's. It's really easy, although you do have to do it fasting (so do it first thing in the morning before breakfast). Eating apparently mucks up the results.

    FeNO stands for Fraction of Exhaled Nitric Oxide. (No, you do not inhale nitric oxide, you exhale it as a normal part of breathing.)

    What this test does is to measure the amount of nitric oxide (NO) in your lungs, which is a marker of inflammation. The less NO, the better your lungs are doing. So yes, with the FeNO test the doctor would be measuring whether you were getting better and whether your ICS was doing a good job at reducing lung inflammation.

    The test simply involves blowing into a little plastic machine for a specific amount of time -- maybe 30 seconds, or a minute. You have to keep the airflow going out at a certain rate. The gizmo my allergist has has a cloud icon and you have to blow to keep the cloud in the middle. I believe they have you do it 2-3 times to make sure the results are consistent.

    The FeNO test is yet another way your doctor can measure how your lungs are doing and how well your asthma is controlled. There's spirometry, FeNO measurement, and simply asking a bunch of questions to see if you're having any symptoms, and when.

    Hope this helps. Feel better soon. Judy

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