AFB: acid-fast bacilli.
* Pyrazinamide may be discontinued after it has been taken for 2 months (56 doses).
¶ Ethambutol may be discontinued when results of drug susceptibility testing indicate no drug resistance to first-line agents.
Δ Worsening chest radiographi findings or clinical manifestations prior to initiation of continuation phase should prompt consideration of drug-resistant tuberculosis or alternate diagnosis; refer to text for further discussion.
◊ Use of once-weekly therapy with isoniazid and rifapentine in the continuation phase, or twice-weekly therapy with isoniazid and rifampin in the continuation phase are no longer recommended except for unusual circumstances to facilitate directly observed therapy. In addition, rifapentine should not be used in patients with extrapulmonary tuberculosis.
§ Patients with drug-resistant isolates should be treated as discussed separately (refer to UpToDate topics treatment of pulmonary tuberculosis and drug-resistant tuberculosis).