The clinical manifestations of pleural effusion are chest pain, dyspnea, chest tightness, telangiectatic breathing, shortness of breath, etc. The clinical symptoms of the primary disease that caused the pleural effusion may also appear, for example, if the pleural effusion is caused by tuberculosis, symptoms of tuberculosis poisoning such as low fever, emaciation, weakness, flushing, cough, etc.; symptoms of chest tightness, palpitation, etc. may appear if it is caused by heart disease; the characteristics of pneumonia-related pleural effusion include cough, fever, coughing sputum, etc.; pain in the liver area may appear if it is caused by liver abscess, etc.; pleurisy Friction sounds can be heard, etc.; large and medium pleural effusions can be characterized by aggravated breathing, light breathing, fast breathing, etc. A normal person has 5 to 15 ml of fluid in the pleural cavity. Pleural effusion is formed when there is an increase in fluid production and a decrease in absorption in the pleural cavity. The diagnosis of pleural effusion can be made based on clinical symptoms, signs, CT of the chest, thoracentesis, etc., to find the cause of pleural effusion disease. Pleural effusion should be actively treated for the cause of the disease, and symptomatic treatment should also be provided. For example, drugs can be used to relieve pain, reduce fever, reduce inflammation, and stop coughing. In short, there are many reasons for the appearance of pleural effusion, and it is necessary to go to the hospital to confirm the treatment and control the disease. Pay attention to more rest, increase nutrition, improve their immunity and prevent infection.