Methacholine Challenge Test in School Children With/Without Asthma RISKA

This study is testing the methacholine challenge test (a breathing test used to detect airway sensitivity) in school-aged children with and without asthma to see how well it works to guide treatment decisions. **You may be eligible if (children with asthma):** - You are between 7 and 15 years old with a doctor-diagnosed asthma - You have been on inhaled corticosteroid treatment for at least 6 months - Your asthma is either well-controlled or poorly controlled but your doctor thinks you need a change in treatment **You may be eligible if (healthy controls without asthma):** - You are between 7 and 15 years old - You have no history of asthma, wheezing, or shortness of breath in the past 2 years **You may NOT be eligible if:** - You were born very prematurely (before 32 weeks of pregnancy) - You have another chronic heart, lung, or neurological condition - You have a serious underlying illness such as cancer - You are taking beta-blocker medication - You have an active immune system disease Talk to your doctor to see if this trial is right for you.