1924
We report a case in which a potential drug interaction resulted in elevated phenytoin levels after initiation of erlotinib therapy in a patient who was receiving phenytoin.
 ( adverse event: resulted in ,  a patient: Subject, elevated phenytoin levels: Effect, a potential drug interaction: Treatment, initiation of erlotinib therapy: Treatment, receiving phenytoin: Treatment, phenytoin: Treatment.Drug, erlotinib: Treatment.Drug, erlotinib: Combination.Drug, phenytoin: Combination.Drug) 
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: resulted in ,  a patient: Subject, elevated phenytoin levels: Effect, a potential drug interaction: Treatment, initiation of erlotinib therapy: Treatment, receiving phenytoin: Treatment, phenytoin: Treatment.Drug, erlotinib: Treatment.Drug, erlotinib: Combination.Drug, phenytoin: Combination.Drug) 