Too often, these days, children who are simply acting out in an attempt to get guidance, discipline, and attention are being diagnosed and drugged just to keep them quiet and more easily managed.
Attention Deficit Disorder, actually, is quite rare. However, Attention Defict Disorder in Adults and in parents who don't want to take the time necessary to raise and discipline children is quite common.
Before you put a child on drugs that may affect him/her for the rest of his/her life, take a look at what YOU, as the rearing parent or guardian are doing that should and MUST be corrected to help raise a child. Clinical diagnoses take time. Raising a child takes time and effort. Putting a label on a child for the mere purposes of making life easier for the parent is easy, takes less time and much less effort.
So, do you say "NO, behave or you'll sit in the corner for a half hour," or do you just shove a pill in their mouths and go back to work after your lunch hour?
It must be difficult raising such an intelligent but disruptive young child. Her symptoms may be a reaction to her parents marital conflicts, or due to Attention-Deficit/Hyperactivity Disorder (ADHD). You may find it helpful to arrange her evaluation by a child psychiatrist.
It sounds like she needs to be evaluated for ADHD. My child acts the very same way and he was evaluated and diagnosed with ADHD. Good luck to you.