The primary anti-TB medicines are Isoniazid (H), Rifampicin(R), Pyrazinamide (Z), Streptomycin (S) and Ethambutol (E). Apart from Streptomycin, the drugs are used in fixed-dose combination (FDC) tablets. Treatment regimens for new cases and retreatment exist for adult patients. Treatment is in two phases: an intensive phase (two or three months) and a continuation phase (four or six months). The aim of the initial intensive phase is to kill the TB bacteria rapidly. The aim of the continuation phase of treatment is to destroy any lingering bacteria that could trigger a relapse. Treatment in the intensive phase is directly observed by a treatment supporter.

http://www.labourguide.co.za/health-and-safety/1374-tb-what-employers-should- know