Sympathetic hyperactivity in patients of bronchial asthma.

The bronchoconstricting and bronchodilating divisions of the autonomic nervous system control airway caliber of lungs. Parasympathetic hyperactivity in asthmatics eventuates in broncho-constriction. Sympathetic activity increases to combat this but fails to control bronchoconstriction due to negligible innervations of the airway smooth muscles although it causes vasoconstriction of blood vessels. In this study the effects of autonomic function test for sympathetic division were seen on selected patients and controls. Our results indicate sympathetic hyperactivity or an increased alpha-adrenergic input in asthmatics.