Reactive airway disease (RAD) is a reversible narrowing of the airways. RAD is sometimes called bronchospasm.

RAD is not a diagnosis. It is a term used until a more specific diagnosis can be made. If the condition lasts more than 6 months, it may be called asthma.

Airways to Lungs
Copyright © Nucleus Medical Media, Inc.

It is not clear what causes RAD. It may be caused by a combination of factors including environment, genetics, and biology.

RAD symptoms are caused by an increased sensitivity of the airways to certain triggers. These triggers cause tightening of the muscles around the airway. At the same time, the lining of the airways swell and produce excess mucus. All of these reactions narrow the airways and make it difficult to breathe.