Welcome to the site.
I am Dr. Kaushik and I will like to help you with your problem.
Well you see racing of mind or racing of thoughts is typically observed in a condition called as Bipolar disorder where in clinical terms it is described as Flight of ideas. Actually usually the ideas/ thoughts are produced in the mind at a particular steady rate but in bipolar disorder these same thoughts and ideas begin to produce at a very fast rate so much so that it appears as if the mind is racing and cluttering with thoughts therefore making the person unable to complete one task at a time but instead the person jumps from one task to another without completing any of them.
At a molecular level in the brain the racing of thoughts / mind which is typical of Bipolar disorder has been considered to be associated with excess of dopamine levels in the brain and therefore this disorder responds well to dopamine blocking drugs like anti psychotics -- Risperdal or zyprexa or Seroquel or abilify.
I hope this helps.
Wish you all the best.
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