The dominance of chemotherapy in TB treatment was established in the late 1960s and early 1970s, and in the two decades since then, this view has been unanimously shared worldwide, with emphasis on the principles that chemotherapy must follow. In China, these principles are summarized as “early, combination, rule, appropriate amount, and whole course”, and the combination and rule are the core of it. 1, short course of treatment (1) determine the shortest course of program: streptomycin, isoniazid, para-aminosalicylic acid, aminothiourea as the representative of the standard chemotherapy program, the whole course of 18-24 months, due to the long duration of drug use, drug toxic side effects, patients have difficulty in adhering to the efficacy of the treatment. The use of rifampicin, a highly effective bactericidal drug, provided the drug basis for short-course chemotherapy, and a large number of comparative studies conducted by the East African2 British Medical Research Association in the mid-1970s on short-course chemotherapy over a 6-month period showed that a short-course regimen with rifampicin was very effective for active TB and did not differ from the standard chemotherapy regimen. Short courses of chemotherapy must be administered with ≥2 bactericidal agents. Clinical trials have found that all chemotherapy regimens shorter than 6 months have failed due to high relapse rates, so the minimum duration of TB treatment should not be < 6 months. (2) Alternative short-course regimens to streptomycin: The short-course regimens for early TB treatment all include streptomycin. To overcome the discomfort associated with long-term deep injection of this drug, another 6-month trial conducted by the East African2 British Medical Research Council showed that the 1-year relapse rate decreased from 5.0% to 2.0% with the combination of isoniazid and rifampicin compared with the addition of streptomycin, but this advantage was minimized by the inconvenience associated with the addition of streptomycin. However, this advantage is offset by the inconvenience of adding streptomycin, so streptomycin can be eliminated during the consolidation phase. The British Thoracic Society reported that when two regimens of isoniazid and rifampicin were compared over a 6-month period, one with pyrazinamide and streptomycin for the first 2 months and the other with pyrazinamide and ethambutol, the recurrence rate was 1/125 in the former group and 3/132 in the latter, with a bacteriologically significant cure rate of almost 100%, suggesting that pyrazinamide + ethambutol could replace pyrazinamide + streptomycin. replace pyrazinamide + streptomycin. (3) Intermittent therapy: In vitro experiments revealed that after exposure to different anti-tuberculosis drugs, M. tuberculosis temporarily stopped growing and multiplying for a certain period of time, called the "delayed growth period", during which M. tuberculosis was not sensitive to drugs, and after this period M. tuberculosis started to grow and multiply again and regained its sensitivity to drugs. The establishment of the theory of delayed growth of tubercle bacilli provides the theoretical basis for intermittent treatment. 6 months of intermittent chemotherapy was conducted in Hong Kong in the 1980s, including about 900 cases, and only one case was ineffective after 6 months. (4) Current short-course regimens: 6 months of intermittent therapy is considered the easiest and most effective short-course regimen available, and is the basis for the current chemotherapy regimens for tuberculosis recommended by the American Thoracic Society and the US Centers for Disease Control. 2. Early treatment Initially treated cases, regardless of their severity, are sensitive to anti-tuberculosis drugs because they have never been treated with anti-tuberculosis drugs. In addition, TB bacilli are actively growing and multiplying in early active lesions, so the drugs can play a maximum bactericidal role, which can rapidly turn sputum bacteria negative and shorten the infectious period. In addition, early treatment can avoid serious destruction of lung tissue and leave no or less sequelae. 3, ensure that patients adhere to the medication The longer the course of chemotherapy, the poorer the patient's compliance, even in a short course of chemotherapy, due to drug side effects, rapid improvement of symptoms and make it difficult for patients to adhere to the program to take medication. Irregular or single-agent use often leads to the development of drug-resistant bacteria, and the strains characteristic of recent TB epidemics in some U.S. cities are often drug-resistant strains. In order to ensure the implementation of chemotherapy regimens, it is necessary to provide systematic health education to patients on the one hand, and to establish corresponding health supervision agencies for intensive period supervision or full management on the other. In recent years, some combination formulations of anti-tuberculosis drugs (isoniazid + rifampin + pyrazinamide and isoniazid + rifampin) have emerged, which are easy to use and help improve patient compliance.