Singular problems exist in the treatment of tuberculosis and other mycobacterial infections. The organisms are intracellular, have long periods of metabolic inactivity, and tend to develop resistance to any one drug. Therefore, combined drug therapy is used to delay the emergence of this resistance. First-line drugs, increasingly used together in all tuberculosis, are isoniazid, ethambutol, rifampin, and pyrazinamide.

See Chapter 9: Pulmonary Disorders for a discussion of these medications.