At times, dyspnea is felt, and this condition is mainly common in diseases of the respiratory system, which lead to impaired ventilation and air exchange, causing a decrease in lung function. Inspiratory dyspnea is caused by inflammatory changes in the pharynx, trachea, and large bronchial mucosa due to congestion, edema, and exudation of inflammatory substances, as well as narrowing of the airway due to foreign body inhalation and tumors; expiratory dyspnea is caused by a decrease in the elasticity of the alveoli and spasm of the bronchi, which can be seen in wheezing bronchitis, bronchial asthma, and emphysema; mixed Dyspnea, mainly caused by extensive lung lesions, such as idiopathic diffuse interstitial pulmonary fibrosis, massive pleural effusion, and severe lung infections.