The change from yellow sputum to white sputum is usually an improvement in the condition. However, it is not possible to generalize about sputum characteristics, and each case needs to be analyzed on its own merits.
In most cases, yellow sputum is caused by bacterial infection. When yellow sputum turns into white sputum, it may be because the inflammation is gradually dissipating, the bacteria or pathogenic microorganisms have been eliminated, and the purulent component of the sputum decreases, and the color gradually turns white, which is a symptom of improvement.
However, it is not scientific to judge whether the condition has improved solely from the aspect of coughing up yellow sputum to coughing up white sputum, but should also be judged in conjunction with other symptoms, laboratory tests and examinations.
Therefore, it is recommended to consult a doctor when this problem occurs.