(1985) suggested that clonidine may be most beneficial in children with ADHD, who are easily emotionally overwhelmed, are anxious, and
have a low frustration tolerance. Clonidine
also stimulates growth hormone release (Leckman et al. 1984), and it causes sedation, so it may be helpful in treating the ADHD of children with FXS who have sleep disturbances, motor tics, or hyperarousal (chap. 1).