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Nasal Nitric Oxide

Patient information A-Z

a picture of an nasal nitric oxide meter and breathing tube with nasal bung being used by a person for performing a nasal nitric oxide measurement.
Nasal nitric oxide meter and breathing tube with nasal bung being used by a person for performing a nasal nitric oxide measurement

Why am I having a nasal nitric oxide test and what is it?

The nasal nitric oxide test is designed to measure the amount of nitric oxide present in your nasal cavity. This gives your doctor valuable information about whether the small hairs in your airways which help clear mucus are working properly and whether there are any blockages.

What does a nasal nitric oxide assessment involve?

Before the test we will ask you to blow your nose. The test involves placing a small bung into the entrance of one of your nostrils and at the same time you breathe through your mouth for 30 seconds. The nasal bung will draw air from your nostril and the device will analyse the amount of nitric oxide. You may be required to perform this in both nostrils.


Please take all medication including inhalers as normal (unless otherwise stated in your appointment letter) The test will last approximately 10 minutes.

What if I am unwell prior to the appointment?

Please contact the department using the phone number stated if you have had a recent chest infection, are currently on a course of antibiotics or have just finished a course of antibiotics for your chest. As a result, it may not be appropriate to perform the test at this time and your appointment may be rescheduled.

If you are unwell please inform the department at the earliest opportunity. However, if you are unwell on the day of the appointment please still call and let us know as this will allow us to rearrange your appointment for a more suitable time.

Who will be present at my appointment?

CUH Addenbrooke’s NHS Trust is a teaching hospital so there may be occasions when a student accompanies your physiologist. We will always seek your permission first.

If you cannot attend your appointment

If you need to rearrange your appointment, or no longer need an appointment, please call the Lung Function department on 01223 217065 at the earliest opportunity. Being able to reallocate appointments helps us to reduce waiting times.


You may be asked for consent to perform tests during your appointment. You will have an opportunity to ask questions before you give consent. In the unlikely event that there are risks related to the tests these will be discussed with you before the test starts.

Test results

After your appointment your test results will be sent to your referring consultant, who will then contact you to discuss the results and the next steps in your pathway.


There are no known risks associated with this test.

Contacts/further information

If you are unsure about any of the information provided in this leaflet or have any other questions then please do not hesitate to contact the lung function department at Addenbrooke’s Hospital on 01223 217065 or alternatively contact clinic 2A on 01223 216645.

Our opening hours are Monday-Friday from 08:30 to 16:30.

We are smoke-free

Smoking is not allowed anywhere on the hospital campus. For advice and support in quitting, contact your GP or the free NHS stop smoking helpline on 0800 169 0 169.

Other formats

Help accessing this information in other formats is available. To find out more about the services we provide, please visit our patient information help page (see link below) or telephone 01223 256998.

Contact us

Cambridge University Hospitals
NHS Foundation Trust
Hills Road, Cambridge

Telephone +44 (0)1223 245151