Pa of ethambutol in RNTCP regime ?

Ans. is 'c' i.e., Bactristatic + detrimental to fast multiplying bacilli Ethambutol It is selectively bacteriostatic and is active against MAC as well as some other mycobacteria. Fast multiplying bacilli are more susceptible With the triple drug therapy it hastens the sputum conversion and also helps to prevent the development of resistance (primary purpose of using it). It inhibits arabinosyltransferase involved in arabinogalactan synthesis, therby interfering with mycolic acid incorporationin mycobacterial cell wall.