Background:
The findings from case reports and patient questionnaire surveys have been interpreted as indicating that administration of stimulants is ill-advised for the treatment of attention-deficit hyperactivity disorder in children with tic disorder.
Methods:
Thirty-four prepubertal children with attention-deficit hyperactivity disorder and tic disorder received placebo and three dosages of methylphenidate hydrochloride (0.1, 0.3, and 0.5 mg/kg) twice daily for 2 weeks each, under double-blind conditions. Treatment effects were assessed using direct observations of child behavior in a simulated (clinic-based) classroom and using rating scales completed by the parents, teachers, and physician.
Results:
Methylphenidate effectively suppressed hyperactive, disruptive, and aggressive behavior. There was no evidence that methylphenidate altered the severity of tic disorder, but it may have a weak effect on the frequency of motor (increase) and vocal (decrease) tics.
Conclusion:
Methylphenidate appears to be a safe and effective treatment for attention-deficit hyperactivity disorder in the majority of children with comorbid tic disorder.