Mannitol test: preparation and procedure.

What the test shows.

The mannitol test is an indirect test: a dry powder makes the airways react in the same way as during exercise. A positive result speaks strongly for asthma.

How to prepare.

• Important information about your medication: only pause if the clinic has asked you to. If the clinic has given you instructions, follow them, and call if you are in doubt.
• Medication pause (the clinic's standard): short-acting reliever (e.g. salbutamol): 8 hours · long-acting beta2 agonist (e.g. formoterol, salmeterol): 36–48 hours · ultra-long-acting beta2 agonist (e.g. vilanterol, indacaterol): 48 hours · ipratropium (e.g. Atrovent): 12 hours · long-acting anticholinergic (e.g. tiotropium): 7 days · antihistamine (allergy medication): 3 days · inhaled corticosteroid and montelukast: as agreed with the clinic.
• Avoid strenuous exercise in the last 4 hours and caffeine (coffee, tea, cola, energy drinks) on the day of the test, smoking/nicotine in the last hour and a large meal in the last 2 hours.
• An airway infection within the last 2–4 weeks: please call and move the appointment.

Duration

The test itself typically takes 30–45 minutes. Expect up to two hours at the clinic in total.

How it is done.

First, spirometry. You then inhale the powder from small capsules in increasing amounts, and your lung function is measured one minute after each step. The test stops at a clear fall in lung function or after the last step.

After the test

If the test is positive, or if you feel tightness in your chest or cough, you are given airway-opening medication, and your lung function is measured again after 10 minutes, so it is back at the starting point before you leave. If the test is negative and you feel well, you are not given medication, but you can have it if you need it.

Side effects

Most people cough during the test; it passes quickly. Brief chest tightness or a slight headache can occur.

When the test cannot be done.

The test cannot be done during pregnancy or with severely reduced lung function, a heart attack or stroke within the last 3 months, uncontrolled high blood pressure or a known aneurysm (a bulge on an artery). Tell us if you are breastfeeding.

Your result

The result is available straight after the test and is reviewed with you before you leave.

What to bring

• Bring ID, for example your health insurance card or driving licence (app versions also count) or your passport. Your CPR number alone is no longer enough.
• Bring an up-to-date medication list and any earlier lung function measurements.
• Always bring your reliever inhaler.
• Arrive in good time, so you are not out of breath when we start.

Background and sources

• The clinic's own source for medication pauses and preparation (version 20-10-2026) and the clinic's test protocols.
• Hallstrand TS et al. ERS technical standard on bronchial challenge testing: pathophysiology and methodology of indirect airway challenge testing. Eur Respir J 2018;52:1801033.
• Aridol (mannitol), summary of product characteristics.

Asthma testing