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    Lung Function Tests

    Lung Function Tests



    What Affects the Test

    Reasons you may not be able to have the test or why the results may not be helpful include:

    • Using medicine that expands the lungs' airways within 4 hours of the test.
    • Using Reference sedatives Opens New Window before the test.
    • Eating food or drinks that contain caffeine before the test.
    • Not being able to breathe normally because of pain.
    • Pregnancy, obesity, or an enlarged stomach (after a large meal, for example).
    • Not being able to follow instructions or make an effort during the tests.



    By: Reference Healthwise Staff Last Revised: Reference April 28, 2011
    Medical Review: Reference E. Gregory Thompson, MD - Internal Medicine
    Reference Mark A. Rasmus, MD - Pulmonology, Critical Care Medicine, Sleep Medicine


    This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Reference Terms of Use. Reference How this information was developed to help you make better health decisions.


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