Tourette syndrome and other tic disorders of childhood.

Tourettte syndrome (TS) is a common, childhood onset neuropsychiatric disorder consisting of multiple motor and one or more vocal tics which persist for more than 1 year. Comorbid psychiatric diagnoses are frequent in this patient population, including attention-deficit/hyperactivity disorder (ADHD) and obsessive-compulsive disorder (OCD). Tics can be simple or complex, and have a tendency to change over time. Tics are preceded by a premonitory sensation, wax and wane in frequency, and are often exacerbated by stress or excitement. Tic severity usually peaks in childhood, and improves in early adulthood. TS is a highly heritable disorder with a polygenic inheritance. The fundamental pathophysiology of TS is not known, although existing evidence suggests that it involves dysfunction of the basal ganglia and frontal cortical circuits, as well as dopaminergic neurotransmission. Treatment of TS involves consideration of symptom severity and comorbidity. In general, comorbid ADHD and OCD lead to greater disability in these patients, and therefore are the initial treatment priority. As treatment for tics does not alter the natural history of the disorder, it is only recommended if the tics are causing disability. Effective treatments to suppress tics include α-adrenergic agonists and antipsychotic medications.