N-acetylcysteine (NAC) for Children With Tourette Syndrome
Condition: Tourettes Syndrome; Tic
MeSH terms: Tourette Syndrome; Syndrome
Intervention: N-Acetylcysteine (NAC); Placebo
Intervention description: 1 600mg capsule twice a day for 2 weeks and then 2 600mg capsules twice a day for the remaining 10 weeks of the trial.; 1 600mg Capsule twice a day for two weeks then 2 600mg capsules twice a day for the remaining 10 weeks of the study. Children receiving placebo will be offered the active intervention after the double-blind portion of the trial.
Intervention MeSH terms: Acetylcysteine; N-monoacetylcystine
Phase: Phase 2
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Enrollment: 31.0
Sex: All
Minimum age: 8 Years
Maximum age: 17 Years
Healthy volunteers: No
Keywords: Tic disorders,; Tourette syndrome; Chronic Tic Disorders

Summary:

      Tourette syndrome is a childhood-onset neuropsychiatric disorder characterized by multiple
      motor and vocal tics that last for at least a year in duration. Currently, there exist
      several effective pharmacological treatments for childhood tics including alpha-2 agonist
      medications (guanfacine and clonidine) and neuroleptics (antipsychotic) medications. These
      medications, however, have significant side-effects and are only partially efficacy in
      treating tics.

      N-acetylcysteine (NAC) is a natural supplement that acts as an antioxidant and glutamate
      modulating agent. NAC has been used safely for decades in doses 20-40 times higher than in
      this trial as an antidote for acetaminophen overdose. The only side-effect commonly seen with
      NAC is nausea and this side-effect is seldom seen in the doses used in this trial.

      NAC has recently been demonstrated to be effective in a double-blind, placebo-controlled
      trial in adults with trichotillomania (chronic hair pulling). Hairpulling is hypothesized to
      be closely related to tics because these conditions (1) have similar clinical characteristics
      -- both groups typically experience urges before engaging in pulling or tics, (2)
      neuroimaging studies suggest they involve similar brain circuits -- the basal ganglia, (3)
      the same pharmacological treatments (neuroleptics) may be effective for both conditions and
      (4) they tend to be inherited together in families. In other trials NAC has evidence of some
      efficacy in treating diverse psychiatric conditions such as bipolar depression, schizophrenia
      and cocaine dependence.

      The investigators are conducting this trial to determine if NAC is an effective treatment for
      tics.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Children aged 8-17 years.

          -  Primary diagnosis of Tourette syndrome or chronic tic disorder.

          -  Duration of tics greater than 1 year.

          -  Significant Current tic symptoms: Current YGTSS score greater than or equal to 22 with
             a TS diagnosis or greater than or equal to 14 with a chronic tic disorder.

        Exclusion Criteria:

          -  Comorbid bipolar disorder, psychotic disorder, substance use disorder, developmental
             disorder or mental retardation (IQ<70).

          -  Recent change (less than 4 weeks) in medications that have potential effects on tic
             severity (such as neuroleptic medications, dopamine agonists, alpha-2 agonists
             (guanfacine, clonidine or prazosin), SSRIs, clomipramine, naltrexone, lithium,
             psychostimulants, or anxiolytics). Medication change is defined to include dose
             changes or medication discontinuation.

          -  Recent change in behavioral treatment for Tourette syndrome or comorbid conditions
             (i.e. OCD) within the last 4 weeks or initiation of behavioral therapy for tics within
             the last 12 weeks.

          -  Asthma requiring medication use within the last 3 months

          -  Known hypersensitivity or previous anaphylactoid reaction to acetylcysteine or any
             components in its preparation

          -  Positive pregnancy test or drug screening test.

          -  Previous use of N-acetylcysteine (dose greater than 600mg for more than 2 weeks)