• Secondary outcomes are improvement in cognitive impairments, since atomoxetine is used for treatment of ADHD and is known to improve cognitive function. [ Time Frame: 24 weeks ] [ Designated as safety issue: No ]
• Vital signs [ Time Frame: Weekly for 24 weeks ] [ Designated as safety issue: Yes ]
• Chemistry panel [ Time Frame: baseline, 10 weeks and 24 weeks ] [ Designated as safety issue: Yes ]

The study investigates the use of Atomoxetine in combination with exercise and a diet support group (Weight Watchers)to treat weight gain associated with Olanzapine or clozapine. All patients must be adults who have been diagnosed with Schizophrenia or Schizoaffective Disorder.

The study is a 6 month double-blind trial of atomoxetine in combination with a Weight Watchers group to help patients lose the weight they have gained taking olanzapine or clozapine. All participants should have been on Olanzapine or clozapine for at least 6 months and gained 7% of baseline weight or have a BMI of 27 or greater. In addition to the group support, participants are provided supervised exercise sessions and medical supervision. Previous studies of the group process alone were successful in helping patients lose weight. It is hoped that the addition of atomoxetine, which is known to cause appetite suppression, will be more effective in helping subjects lose weight. All subjects will receive either atomoxetine or placebo during the 6 month study.

• Behavioral: Diet support group
• Behavioral: Group counseling and exercise

• Active Comparator: Atomoxetine titrated up to 120 mg/day by week 8 and continues at 120 mg/day through week 24.
• Placebo Comparator: Placebo medication, diet support group weekly and exercise sessions 3 times/week

Inclusion Criteria:

• Schizophrenia or schizoaffective Disorder
• Taking olanzapine or clozapine for at least 6 months
• Weight gain of 7% over baseline or BMI greater than or equal to 27

Exclusion Criteria:

• Current treatment with methylphenidate, clonidine, tricyclic antidepressants, bupropion and venlafaxine
• Treatment with other medications known to cause weight gain unless weight stable on medication for 6 months
• Current treatment with other medications for weight loss unless weight stable for 6 months
• Mental Retardation
• Alcohol or Substance Dependence within the last 6 months
• Pregnancy
• Alcohol or Substance Abuse within the lat month
• Uncontrolled hypertension defined as a blood pressure exceeding 140/90 on three consecutive readings despite adequate treatment