Yes. Using a stimulant--Adderall, Ritalin (methylphenidate),
Concerta (extended release methylphenidate, and others--along with
the atypical antipsychotics (such as Risperdal, Seroquel, Zyprexa,
Ability) is often done, usually if aggression is present with the
ADHD or if mood symptoms, such as bipolar symptoms are present.
There can be side effects associated with this combination; this
usually occurs when one or the other is removed or started. (in the
realm of motor movements--known as dyskinesias). Folks on a stable
combination don't usually have this problem. This problem
particular problem goes away once doses are adjusted. Most folks
don't experience this particular side effect.