Does Eptoin Induce Sleep And Cause Drowsiness?

hi..my father is a gutb patient detected in sept 2009 and has undergone bypass in oct 2008..now its mdrtb nd he s taking ethionamide 250 mg twice a day,zanocin,rcinex,solonex,benadon,eptoin 100mg twice a day,tryptomer 20 mg at nite,lyrica 75 mg twice a day.now he is feeling damn sleepy and always drowsy,can he withdraw eptoin or any other medicine,since he withdrew streptomycin four days back