<prompt> First line ATT in childrenStreptomycinPyrazinamideEthionamide1 2  <response>: The first line drugs in ATT are effective with minimal toxicity and include isoniazid,rifampicin,ethambutol,streptomycin and pyrazinamide.Ethionamide is a second line drug. In a view of increasing INH resistance, use of three drugs INH, Rifamipicin , and ethambutol instead of two INH and rifampicin is suggested during the continuous phase . Reference : Ghai essential pediatrics 9 th edition Page 249 