A condition where the airways are affected by inflammation is referred to as bronchial asthma. Affected people have complaints of attacks of shortness of breath in particular during the night and early morning, a whistling sound while breathing in and out, coughing, and coughing up glassy viscous mucus. Certain messengers have inflammatory effects on the airways, resulting in swelling of the bronchial walls. The respiratory passages become restricted and the secretion of mucus with a viscous consistency increases.