Adults 1) Inhibition of Mycobacterium avium intracellulare complex (MAC) infection in immunocompromised patients with CD4 lymphocyte count below 200 cells/μL : As rifabutin, 300mg(titer) is administered once a day. For patients with nausea, vomiting, or gastrointestinal tract abnormalities, it is effective to take 150mg(titer) twice a day with food. 2) Infectious disease caused by nontuberculous mycobacteria : It is administered in combination with 450~600mg (titer) per day. The administration is continued for up to 6 months after confirming negative. 3. Pulmonary tuberculosis 150~450mg (titer) per day is administered continuously for at least 6 months. In general, this drug should be administered in combination with other antimycobacterial drugs that do not belong to the rifamycin. 2. Patients with severe renal failure (creatinine clearance less than 30mL/min): Reduce the dose to 1/2 and administer it.