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Pulmonary Function Test: Exhaled Nitric Oxide (eNO)

Test Procedure

eNO is measured by having your child place his or her mouth around a single use, disposable, filterable mouthpiece. Your child will be asked to inhale deeply and exhale slowly through the mouthpiece.

Time of the Test

The test takes about two minutes. With explanation and practice, testing may take up to 10 minutes.

Preparing Your Child for the Test

Your child should not eat or drink anything for one hour before testing. Certain foods and drinks may be high in nitrates or preservatives and can elevate eNO levels.

Possible Side Effects

There are no side effects and your child may resume normal activities after testing.