803
Of the 15 patients treated with tizanidine and mexiletine, 4 suffered tizanidine-induced adverse effects such as drowsiness and dry mouth in the retrospective survey.
 ( adverse event: induced ,  15 patients: Subject, 4: Subject, 15: Subject.Population, drowsiness and dry mouth: Effect, tizanidine and mexiletine: Treatment, tizanidine: Treatment.Drug, mexiletine: Treatment.Drug, tizanidine: Treatment.Drug, tizanidine: Combination.Drug, mexiletine: 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: induced ,  15 patients: Subject, 4: Subject, 15: Subject.Population, drowsiness and dry mouth: Effect, tizanidine and mexiletine: Treatment, tizanidine: Treatment.Drug, mexiletine: Treatment.Drug, tizanidine: Treatment.Drug, tizanidine: Combination.Drug, mexiletine: Combination.Drug) 