Present chemotherapy of tuberculosis.

Significant advances in the treatment of tuberculosis have occurred with the introduction of short-course therapy using isoniazid and rifampin throughout therapy. The addition of pyrazinamide to the initial phase of therapy permits shortening of the total duration of treatment to 6 months for most patients. This regimen is well tolerated, results in rapid disappearance of bacilli from the sputum, and has a low rate of relapse. Ethambutol should be added to this regimen for any patient with an increased chance of having isoniazid resistant disease. Periodic culturing of the sputum from patients with pulmonary tuberculosis is essential for monitoring response to therapy. Patient noncompliance with therapy is the most common cause of treatment failure, and any patient suspected of being noncompliant should receive directly observed therapy. For this purpose, most treatment regimens may be adapted to twice weekly administration.