Objective To investigate the efficacy of initial polytherapy in the patients with newly diagnosed infantile spasm by evaluating the ambulatory electronecephalogram (EEG) profiles and serum neuron specific enolase ( NSE ) level.Methods Data from 108 cases of newly diagnosed infantile spasm from Sep.2007 to Nov.2010 in the Department of Pediatrics,the First Hospital of Jilin University,were respectively analyzed for the EEG profiles and serum NSE level.The patients were treated with multiple drugs.Results ( 1 )After treatment,EEG showed normal shape in 56 cases ( 62.2％ ),sporadic sharp and slow waves without hypsarrhythmia in 32 cases( 35.6％ ),and hypsarrhythmia in 2 cases (2.2％).The overall effective rate was 97.8％.(2) Serum NSE in 35 seizure-free cases were examined at the time points of hospital admission,48 hours and one month after seizure cessation,respectively.NSE level was significantly decreased at 48 hours after seizure control than that at hospital admission ( t =6.54,P ＜ 0.05 ) ; NSE at one month after seizure free was further decreased compared with that at admission point ( t =9.29,P ＜ 0.05 ).Conclusion Polytherapy for infantile spasms can ameliorate the abnormal EEGs.NSE level is decreased after seizure cessation.Intelligence is improved 6 months after seizure free and polytherapy may improve the prognosis of the children with infantile spasms.