Acute laryngitis is an acute non-specific inflammation of the laryngeal mucosa and vocal cords, usually within 1 month, and is one of the common acute infectious diseases of the respiratory tract, accounting for 1% to 2% of otorhinolaryngological diseases. Acute laryngitis generally refers to acute laryngitis that occurs in adults. It is often secondary to acute rhinitis and acute pharyngitis. The incidence is higher in men than in women. It occurs mostly in winter and spring. Pediatric acute laryngitis has its own peculiarities, which seriously affects breathing, and the condition is more serious and changes faster. The main symptom of acute laryngitis is hoarseness, which is mainly due to congestion and edema of the mucous membrane of the vocal cords. In mild cases, the voice quality is less rounded and brighter, and the tone is lower and coarser than before; in severe cases, the voice is hoarse and the vocal effort is difficult, or worse, the voice can only be whispered, or completely lost. Patients feel discomfort, dryness, burning and foreign body sensation in the larynx, and there may be slight pain in the larynx and front of the trachea. 3, cough Because of the laryngeal mucosa inflammation secretions increase, often cough, initially dry cough without sputum, to the late larynx there are mucopurulent secretions, because of the thick, often not easy to cough up. If the secretion adheres to the surface of the vocal cords, it can aggravate the hoarseness of the voice. A few adults with severe acute laryngitis may have inspiratory dyspnea due to mucosal edema in the laryngeal cavity, which is common in subglottic acute laryngitis, as the subglottic region is a narrow space, and if the mucosa is highly edematous, the airway is bound to be obstructed. 5. Systemic symptoms Adults generally have mild symptoms of systemic toxicity. More severe bacterial infections may be accompanied by fever, chills, lethargy, loss of appetite and other systemic symptoms. 6. Infection of adjacent organs As the mucous membranes of the respiratory tract continue each other, acute laryngitis can be a downstream infection of acute rhinitis or acute pharyngitis, so it is often accompanied by inflammatory symptoms of the nose and pharynx. Acute laryngitis can also be accompanied by symptoms of lower respiratory tract infections such as trachea, bronchus and lung.