ResultsBy Mayo Clinic staff
Higher than normal levels of nitric oxide generally mean your airways are inflamed — a sign of asthma.
- Levels under about 20 parts per billion in children and under about 30 parts per billion in adults are considered normal.
- More than 25 parts per billion in children and 35 parts per billion in adults may signal airway inflammation caused by asthma.
Keep in mind, nitric oxide test results can vary widely from person to person. When interpreting test results, your doctor will consider a number of other factors. These may include:
- Results of other tests, such as peak flow tests or spirometry tests
- Past nitric oxide test results
- Your asthma signs and symptoms
- Any medications you take
- Whether you have a cold or the flu
- Whether you have hay fever or other allergies
- Dinakar C. Exhaled nitric oxide in pediatric asthma. Current Allergy and Asthma Reports. 2009;9:30.
- Budev MM, et al. Battery of maneuvers. In: Carey WD, et al. Cleveland Clinic: Current Clinical Medicine. 2nd ed. Philadelphia, Pa.: Saunders Elsevier; 2010. http://www.mdconsult.com/books/page.do?eid=4-u1.0-B978-1-4160-6643-9..00169-7--s0020&isbn=978-1-4160-6643-9&sid=1098987055&type=bookPage§ionEid=4-u1.0-B978-1-4160-6643-9..00169-7--s0135&uniqId=230624543-7#4-u1.0-B978-1-4160-6643-9..00169-7--s0135. Accessed Dec. 23, 2010.
- Barnes PJ, et al. Exhaled nitric oxide in pulmonary diseases. Chest. 2010;138;682.
- Li JT (expert opinion). Mayo Clinic, Rochester, Minn. Jan. 4, 2010.