421
She was receiving phenytoin sodium 300 mg/day; carbamazepine 200 mg four times daily had been discontinued four days before admission because of leukopenia.
 ( adverse event: because ,  leukopenia: Effect, carbamazepine 200 mg four times daily: Treatment, carbamazepine: Treatment.Drug, 200 mg: Treatment.Dosage, four times daily: Treatment.Freq) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: adverse event,potential therapeutic event, Arguments type: Treatment.Disorder,Treatment.Time_elapsed,Treatment.Dosage,Subject.Race,Treatment.Drug,Treatment.Route,Subject.Disorder,Treatment.Freq,Treatment,Effect,Subject.Population,Treatment.Duration,Combination.Drug,Subject,Subject.Age,Subject.Gender. 
Text: {0} 
Answer:
 ( adverse event: because ,  leukopenia: Effect, carbamazepine 200 mg four times daily: Treatment, carbamazepine: Treatment.Drug, 200 mg: Treatment.Dosage, four times daily: Treatment.Freq) 