Introduction
The mannitol challenge test is used to identify airway sensitivity and to assist in the diagnosis of asthma. Mannitol is a type of sugar and in this test is used in an inhaled form.
About the test
To help in the review and management of your child’s current condition, your doctor believes that an airway challenge test is needed.
How is the test performed?
Your child will breathe in accumulated doses of a medication called Mannitol, over a number of levels, from a device similar to an asthma puffer.
Between every level/administered dose your child will have 1 minute rest.
At the start of the test and after each dose, your child will be asked to perform a breathing test that measures how quickly and how much they can blow out after a big breath in.
The breathing test will be repeated to ensure the biggest value is recorded, before moving on to the next dose of Mannitol.
If there are any large changes in your child’s breathing, the test will be stopped, and your child will be offered Ventolin to reverse any symptoms that may have started. A doctor may also listen to your child’s chest to see if they can hear any wheeze.
The whole process is usually finished in 45-60 minutes.
There are no delayed or late effects.
How safe is the test?
Testing using Mannitol is a safe and very common test performed in children.
There have been no reported serious side effects following the use of Mannitol.
Approximately 30% of patients find that the test causes mild symptoms of cough, shortness of breath, chest tightness, wheeze, headache, or dizziness. These symptoms rarely cause a problem.
If your child develops any such symptoms that cause discomfort or concern, they are encouraged to tell the scientist doing the test. These symptoms can usually be relieved at the end of the test by coughing, or by taking Ventolin for any shortness of breath, or wheezing.
Does my child have to do the test?
Your child does not have to perform the test and you, or your child, can ask to discontinue the testing at any time.
Your decision not to perform the testing or discontinue testing will not affect the medical care your child receives from the hospital or your referring doctor.
Medication restrictions
To make sure the results are accurate, please restrict your child’s medications as follows.
6-8 hours before test, stop taking:
- Ventolin, Asmol, Bricanyl (Short Acting Beta2 Agonists )
12 hours before the test, stop taking:
- Atrovent (Ipratropium Bromide)
24 hours before the test, stop taking:
- Nuelin (Theophylline)
4 days before the test, stop taking:
- Pulmicort, Qvar, Becotide, Flixotide, Alvesco (Inhaled Corticosteroids)
- Seretide, Symbicort, Breo Ellipta (Inhaled Corticosteroids with long acting Beta2 Agonists)
- Serevent, Foradile, Oxis (Long acting Beta2 Agonists)
- Spiriva (Tiotropium Bromide)
- Benadryl, Zyrtec, Telfast, Claratyne (Antihistamines)
- Singulair (Leukotriene receptor antagonists)
Please note: In some cases, your doctor may ask your child to take their prescribed preventer on the day of the test (e.g. Seretide, Symbicort, Breo etc.) to check your child’s stability on that preventer. If this is the case, please ignore the medication restrictions except for relievers (e.g., Ventolin) which must not be used on the day of the test.
On the day of the test
Caffeine restrictions
Please don’t give your child coffee, tea, cola and other products containing caffeine. These can reduce airway sensitivity.
Your child should not do any vigorous exercise on the day of the test. This is because vigorous activity can trigger acute airway narrowing and may hide other symptoms
If your child is unwell
If your child is having breathing difficulties or needs their breathing medication on the day of the test, then they should take their medication and we will rebook the test for a later date. Your child’s safety comes first.
Please reschedule the test if your child is unwell with any upper respiratory symptoms at the time of testing as this can cause inaccurate test results.