1202
Attempts were made to stop and then restart the theophylline therapy at progressively lower doses; however, with each attempt, the patient's reaction to the drug became more toxic, with serum theophylline levels ranging between 99.9 and 149.9 micromol/L (18 and 27 microg/mL).
 ( adverse event: became ,  patient: Subject, reaction to the drug became more toxic: Effect, theophylline therapy: Treatment, theophylline: Treatment.Drug, 99.9 and 149.9 micromol/L: Treatment.Dosage, 18 and 27 microg/mL: Treatment.Dosage) 
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: became ,  patient: Subject, reaction to the drug became more toxic: Effect, theophylline therapy: Treatment, theophylline: Treatment.Drug, 99.9 and 149.9 micromol/L: Treatment.Dosage, 18 and 27 microg/mL: Treatment.Dosage) 