Patients with old tuberculosis should not be too anxious when they develop a cough because the cough itself can be caused by a variety of reasons. If the cough is less than two weeks old and the coughing symptoms are mild with no other obvious accompanying symptoms, no special treatment can be done for the time being, and the patient should drink more water and rest. If the cough is obvious, the patient can be treated with cough suppressants. If the cough is accompanied by sputum, fever, chest tightness, and other discomforts, the patient can be treated symptomatically while having routine blood, sputum bacterial examination and lung imaging to determine whether the cough is infectious. If the cough lasts for more than two weeks, regardless of whether the symptoms are obvious or not, tuberculosis-related tests such as sputum for antacid bacilli, sputum tuberculosis culture, lung imaging, blood sedimentation, tuberculosis antibody, tuberculin skin test, infectious T-cell test, and tuberculosis gene test should be completed to clarify whether the tuberculosis is recurrent. If it is determined to be a recurrence of TB, regular anti-TB treatment and completion of the anti-TB regimen should be performed, and the possibility of drug-resistant TB needs to be ruled out based on the final TB culture results.