Ciclesonide is used to prevent and reduce the symptoms (wheezing and shortness of breath) caused by asthma. Controlling asthma symptoms may decrease time lost from work or school. This medication belongs to a class of drugs known as corticosteroids. It works by reducing the swelling of the airways in the lungs to make breathing easier. This medication must be taken regularly to be effective. It does not work right away and should not be used to relieve sudden asthma attacks. If an asthma attack occurs, use your quick-relief inhaler as prescribed. Keep track of how often you need to use your quick-relief inhaler, and tell your doctor. If your quick-relief inhaler does not seem to work as well, if you need to use more than usual of your quick-relief inhaler for 2 or more days in a row, or if you need to use more than one full canister of your quick-relief inhaler over a 2-month period, seek immediate medical attention.