Co-occurring psychiatric disorders in children and adolescents with Tourette syndrome.

More than half of all children and adolescents with Tourette syndrome show evidence of psychiatric comorbidity, exhibiting symptoms of attention-deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder, and other anxiety and mood disorders. Although the prevalence of co-occurring conditions varies depending on the clinical setting, it is crucial for clinicians to be familiar with these disorders because they are often more impairing than tics and can influence the initial treatment choice. Left untreated, these conditions can negatively affect important developmental outcomes, such as academic and social functioning. We review the most common co-occurring disorders, the relationship of these co-occurring disorders to Tourette syndrome, and treatment recommendations for co-occurring conditions when tic symptoms are present.