The U.S. Food and Drug Administration has approved 3 medications, atomoxetine and the extended-release formulations of amphetamine salts and dexmethylphenidate, for the treatment of adult attention-deficit hyperactivity disorder (ADHD). Different formulations of the same drugs, as well as other agents and cognitive-behavioral therapy, have been tested to determine efficacy in ADHD alone and in ADHD with comorbid substance use disorders, mood disorders, and anxiety disorders. A deficit in research exists in regard to these comorbidities in adults with ADHD.