Diagnostic Parameter, Tourette's syndrome

Tourette's Disorder

This is a rare disorder characterized by repetitive muscle movements and vocal outbursts. The main diagnostic criteria is as follows:

At some time during the illness, though not necessarily at the same time, the patient has had both of:

At least one vocal tic (A tic is a motor movement or vocalization that is nonrhythmic, rapid, repeated, stereotyped and sudden) and

Multiple motor tics:

For longer than 1 year, these tics have occurred many times each day, nearly every day or at intervals.

During this time, the patient never goes longer than 3 months without the tics.

These symptoms cause marked distress or materially impair work, social or personal functioning.

The symptoms begin before age 18. Approximately 1% of mainstream schoolchildren may be affected. Onset occurs with motor tics usually followed by vocal tics.

The symptoms are not directly caused by the effects of a general medical condition (such as Huntington's disease or a postviral encephalitis) or substance use (such as a CNS stimulant).