ABSTRACT
Cough Cough is an explosive expiration that clears and protects the airways. It is one of the most common presenting complaints encountered in an outpatient practice. A cough is under both voluntary and involuntary control. The latter is the cough reflex, which has five components: cough receptors, afferent nerves, cough center (medulla), efferent nerves, and effector organs. The afferent limb of the cough reflex includes the sensory branches of the trigeminal, glossopharyngeal, and vagus nerves. Inflammatory, mechanical, chemical, or thermal stimulation of the receptors and sensory pathways can trigger cough. The efferent limb includes the recurrent laryngeal and spinal nerves that innervate the expiratory and laryngotracheobronchial musculature. Lesions in the nose, ears, pharynx, larynx, bronchi, lungs, pleura, or abdominal viscera can cause cough.
