ADHD and Coexisting Conditions: Tics and Tourette Syndrome (WWK
5A) Can't find what you're looking for? Our health information
specialists are here to help. Contact us at 800-233-4050 or
online. WWK refers to the What We Know series of information
sheets on ADHD. See the complete list. See the PDF version of
this sheet. Attention-deficit/hyperactivity disorder (ADHD) is a
common neurobiological condition affecting 5-8 percent of school
age children1,2,3,4,5,6,7 with symptoms persisting into
adulthood in as many as 60 percent of cases (i.e. approximately
4% of adults).8,9 However, in only about 30 percent of these
children, is ADHD the only diagnosis. Thus, two thirds of
children with ADHD have at least one other coexisting
condition.10 Any disorder can coexist with ADHD, but certain
disorders seem to occur more commonly.11 These disorders include
tics and Tourette syndrome. It is important to diagnose and, if
necessary, to treat these other conditions in addition to the
ADHD, because, just as untreated ADHD c