The results of a 3-year follow-up of 598 patients with newly-diagnosed and 152 with recurrent pulmonary tuberculosis were studied. It was found that in both these groups, with or without lung tissue decomposition, the addition of rifampicin to the given combination of drugs resulted in a higher rate and earlier improvement of health; lower percentage of persons with aggravating process and fatal outcomes; and shorter period of in-patient treatment and temporary disability. As a consequence, direct and indirect economic loss caused by one patient receiving rifampicin appeared to be less in all groups of the patients compared to that caused by the subjects not on this drug. An economic effect produced by adding rifampicin to the given combination of drugs was 11.1-27.5 times higher than additional expenditures.