Large amount of white foamy sputum is mostly seen in bronchitis, infectious lung diseases, acute left heart failure, and alveolar cell carcinoma. In acute and chronic bronchitis or pulmonary infections, patients can present with large amounts of white foamy sputum, which can be accompanied by increased leukocytes or neutrophils in routine blood, and peribronchitis or intra-pulmonary sheet exudates as seen on lung CT. Treatment with antibiotics is effective, and community-acquired infections can be treated with drugs such as cefaclor or moxifloxacin. Patients with left heart failure can also have large amounts of white foamy sputum and in severe cases can have pink foamy sputum. This is mainly due to the increase of pulmonary artery pressure caused by a large amount of blood stagnation in the pulmonary artery after the heart pump function is impaired, which leaks into the alveoli and forms a large amount of foamy sputum. Patients with alveolar cell carcinoma are characterized by a large amount of white foamy sputum. Tumor cells or anomalous cells can be found in the sputum.