BRONCHITOL is only for adults (18 years of age or older) who have passed the BRONCHITOL Tolerance Test (BTT). Before your doctor prescribes BRONCHITOL, a trained healthcare practitioner must administer the BTT. This test will identify whether you are hyperresponsive, or sensitive, to mannitol, the main ingredient in BRONCHITOL. If during the test the measurements of your lung function fall below a certain level, or you experience bronchospasm, then you should not be prescribed BRONCHITOL. In clinical trials, 92% of adult patients passed the BTT. The BTT also lets you practice the correct way to use the inhaler and take the medication while under the supervision of a healthcare practitioner. Talk to your doctor if you have questions about starting treatment.