Study of Clonidine on Sleep Architecture in Children With Tourette's Syndrome (TS) and Comorbid ADHD

Inclusion Criteria: Males or females Meet the DSM-III-R criteria for Tourette syndrome based on the assessment of a study psychiatrist and the presence of comorbid Attention Deficit Hyperactivity Disorder (ADHD) according to DSM-IV diagnostic criteria A negative history of psychiatric illness that requires treatment. Medication free for a minimum period of six (6) weeks at the time of entry into the study Between the ages of 9:0 years and 14:11 years An initial screening score on the Children's Aggression Scale-Parents Version of at least +1SD above average on at one or more of the four subscales. Adequate English language comprehension and production (sufficient to respond to questions from the investigators) Be able and willing to cooperate with the study protocol All parents/caregivers will provide consent and subjects (children/adolescents) will give their informed assent prior to participating in any study procedures. Known history of sleep disturbances (children will be considered to experience sleep disturbances if their sleep latency regularly exceeds 30 minutes; to have a general poor quality of sleep if there are frequent awakenings (>2 nightly), nightmares or restlessness; or if they experience difficulty awakening, marked difficulty with arousal or consistent oversleeping. For the purposes of this study, a disturbance in sleep is considered only if it is chronic (lasting more than one month) and frequent (two or more times per week). Exclusion Criteria: *Evidence of Pervasive Developmental Disorder, known seizure disorder, history of severe head trauma, post-traumatic stress disorder, depression, known organic basis for a sleep disorder and/or an estimated Full Scale Intellectual Quotient below 85