Whether the transition from a dry cough to sputum is a remission or an aggravation needs to be analyzed according to the specific cause of the disease. If the cough is due to the inability to cough up phlegm in the early stages of a dry cough, the appearance of coughing up phlegm at a later stage is regarded as a reduction of the condition; if there is no phlegm in the lungs themselves at the beginning, and phlegm appears at a later stage, this indicates that there may be a secondary bacterial infection, which is an aggravation of the condition. 1. Decrease: If the cough caused by tuberculosis is dry at the beginning, it is actually due to the dryness of the respiratory tract and the thick mucus phlegm, which makes it impossible to cough out the phlegm, and is manifested as a dry cough. Later, through the use of medication, phlegm and cough, the amount of phlegm increases, stimulating the respiratory muscles to produce coughing action, coughing up phlegm, which is conducive to the improvement of the condition. This situation is alleviated. 2. Exacerbation: such as acute upper respiratory tract infection, initially viral infection, no sputum, later due to the progression of the disease, secondary bacterial infections, sputum can appear, at the same time will be combined with yellow sputum or bloody sputum and so on, at this time for the aggravation of the condition, the need to be actively dealt with. From dry cough to sputum, there may be other reasons, it is recommended to consult a doctor in time to identify the cause, under the guidance of the doctor’s scientific treatment.