Patient description: The patient is a 32-year-old obese woman who came to the clinic with weight concerns. She is 165 cm tall and her weight is 113 kg. She is complaining of sleep apnea, PCO and dissatisfaction with her body shape. She is a high-school teacher married for 5 years. She doesn't use any contraceptive methods for the past 4 months and she had no prior pregnancies. She doesn't smoke or use any drugs. She likes to try diets and exercise to lose weight. She completed the four square step test in 14 seconds. Her BP: 130/80, HR: 195/min and her BMI is: 41.54. Her labs: FBS: 98 mg/dl TG: 150 mg/dl Cholesterol: 180 mg/dl LDL: 90 mg/dl HDL: 35 mg/dl Her cardiac assessment is normal. Her joints and ROM are within normal.

Clinical trial eligibility criteria: eligible ages (years): 18.0-55.0,  Drug Binding to DAT Receptors Signed written informed consent to participate in the study. 2. Age: 18 -45, inclusive 3. If female, non-pregnant, non-nursing with a negative serum pregnancy test. 4. Female subjects will agree to use an acceptable and effective form of birth control during the course of their study participation. 5. Supine and standing blood pressure < 150/90 mmHg. 6. Heart rate, after resting for 5 minutes, within the range 46-90 beats/min. 7. Right handed  Diagnosis of any psychotic disorder, bipolar disorder, severe depression, severe anxiety, or Autism. Subjects with mild mood, oppositional, conduct, and anxiety disorders may be permitted to participate if considered appropriate by the investigator. 2. Scores of Baseline Scales Hamilton Depression Scale > 12 (out of a possible 67 on the 21-item scale)[18] Beck Depression Inventory > 19 (out of a possible 63 on the 21-item scale)[19] Hamilton Anxiety Scale > 21 (out of a possible 56 on the 14-item scale) [20] 3. Subjects with motor tics or with a family history or diagnosis of Tourette's Syndrome. 4. History of head trauma with loss of consciousness, organic brain disorders, seizures, or neurosurgical intervention. 5. Any clinically significant chronic medical condition, in the judgment of the investigator. 6. In the judgment of the investigator, has a mental impairment as evidenced by an I.Q. <75. 7. Exposure to dopamine receptor antagonists within the previous three (3) months. 8. Exposure to radiopharmaceuticals within four (4) weeks prior to PET scan. 9. Subjects receiving psychotropic medication including MAO inhibitors within the past 6 to 12 months. 10. Any clinically significant abnormality in the screening laboratory tests, vital signs, or 12 lead ECG, outside of normal limits. 11. Any pre-existing structural cardiac abnormalities. 12. A history or known family history of long QT syndrome or QTc >450 ms (males) or >470 ms (females). 13. Any family history of cardiac sudden death. 14. QTc prolongation of QTc > 450 ms (male) or 470 ms (female), hypertension or cardiac arrhythmia, or increased heart rate for age in the judgment of the investigator at screening. 15. A history of cardiac structural abnormality 16. Any woman of childbearing potential who is seeking to become pregnant or suspects that she may be pregnant. 17. Subjects with a known recent history (within the past six (6) months) of illicit drug or alcohol dependence. 18. Subjects diagnosed with glaucoma. 19. Subjects at risk for MPH toxicity (e.g. individuals with arrhythmias, coronary artery disease, etc.)