Prevention of Stimulant-Induced Euphoria With an Opioid Receptor Antagonist

Study start date: September 1, 2012

Inclusion Male and female outpatients age 18-30 diagnosis of ADHD by DSM-IV, per clinical evaluation and confirmed by structured interview likeability response (> 5) on Question #2 of the DRQ-S after an initial test dose of 60 mg of IR MPH. Baseline ADHD severity of > 20 on the Adult ADHD Investigator System Report Scale (AISRS) Able to participate in blood draws and to swallow pills. Subjects must be considered reliable reporters, must understand the nature of the study and must sign an informed consent document Exclusion Any current (last month), non-ADHD Axis I psychiatric conditions Ham-D > 16, BDI > 19, or Ham-A > 21 Any clinically significant chronic medical condition any cardiovascular disease or hypertension Clinically significant abnormal baseline laboratory values I.Q. < 80) Organic brain disorders Seizures or tics Pregnant or nursing females Clinically unstable psychiatric conditions (i.e. suicidal behaviors, psychosis) Current or recent (within the past year) substance abuse/dependence patients on other psychotropics Current or prior adequate treatment with MPH known hypersensitivity to methylphenidate Current opioid use (by history and urine screen) or potential need for opioid analgesics during the study acute hepatitis or liver failure (baseline blood tests).