For about 20 years, the recommended duration of daily chemotherapy for tuberculosis has been 18 to 24 months. Indeed, it seemed very unlikely that the duration could be shortened without a considerable increase in relapses. The difficulties with such prolonged daily therapy are many: (1) cooperation and compliance are difficult to maintain for such a prolonged course of therapy; (2) ingestion of drugs for 18 months to two years is psychologically demanding on the patient, long after his apparent clinical recovery; (3) potential drug toxicity increases with duration of therapy; (4) the cost of therapy increases with its duration; (5) developing countries are unable to afford such prolonged therapy; and (6) relapses increase as patients fail to take the full course of therapy, thus risking an increase in resistant bacilli in the population.
Recently, an important advance has been made by the discovery that a combination of the two bactericidal
Dutt AK, Stead WW. Short-Course Treatment Regimens for Patients With Tuberculosis. Arch Intern Med. 1980;140(6):827–829. doi:10.1001/archinte.1980.00330180101028