Attention deficit hyperactivity disorder predominantly inattentive (ADHD-PI), formerly attention deficit disorder (ADD), is one of the two types of attention deficit hyperactivity disorder (ADHD). The term was formally changed in 1994 in the new Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV), to "ADHD predominantly inattentive" (ADHD-PI or ADHD-I) - though the term 'attention deficit disorder' is still widely used. 'Predominantly Inattentive' is similar to the other subtypes of ADHD except that it is characterized primarily by inattentive concentration or a deficit of sustained attention, such as procrastination, hesitation, and forgetfulness; it differs in having fewer or no typical symptoms of hyperactivity or impulsiveness. Lethargy/fatigue is sometimes reported, but ADHD-PI is a separate condition from the proposed cluster of symptoms known as Sluggish cognitive tempo.The three most popular ADHD medications in order are: Amphetamine mixed salts for dopamine and norepinephrine basically balanced, Methylphenidate for a dopamine emphasis, and Atomoxetine for a norepinephrine emphasis.