咳嗽本身是一种保护性的生理反应,当呼吸道受到某种刺激,如有害的烟雾和气体、痰液、异物等,刺激通过传入神经引起咳嗽中枢兴奋,便导致了咳嗽。它可以避免上述有害物质深入呼吸道而对人体造成伤害。所以在一般情况下,轻度咳嗽时 Cough itself is a protective physiological reaction, when the respiratory tract by some kind of stimulation, such as harmful fumes and gases, sputum, foreign body, stimulate the cough center through the afferent nerve stimulus, it will lead to cough. It can avoid the above harmful substances into the respiratory tract and cause harm to the human body. So under normal circumstances, mild cough