This study will determine the effectiveness of administrating a dose of cholecystokinin during a binge eating episode in reducing this eating behavior in people with bulimia nervosa.

Bulimia Nervosa (BN) is a serious eating disorder that is characterized by frequent uncontrolled eating binges. These binges are often followed by compensatory behavior, including the following: self-induced vomiting; misuse of laxatives, diuretics, enemas, or other medications to induce purging; fasting; or excessive exercise. If left untreated, BN can lead to many serious health issues: tooth decay; irregular menstruation; bowel damage; constipation; heart and kidney disease; intestinal damage; puffiness, especially in the face and fingers; increased hair growth on the face and body; and mineral imbalances in the body. Cholecystokinin (CCK) is a hormone that is released by the small intestine, and functions as a trigger for digestion and hunger suppression. People with BN often have disturbances in the release of CCK, which may contribute to their binge eating behavior. This study will determine the effectiveness of administrating a dose of CCK during a binge eating episode in reducing this eating behavior in people with BN.

This study will enroll females with BN and healthy females without BN. Interested participants will first report to the study site for an interview about their feelings on their eating habits. If eligible, participants will report to the study site at 9 A.M. on 4 days. Upon arrival, they will receive a standardized breakfast of apple juice and an English muffin with butter. Participants will then return 2.5 hours later to start an IV and begin infusion with a normal saline solution. After 10 minutes of saline infusion, participants will eat a small bowl of tomato soup, followed 20 minutes later by a 15-minute infusion of either saline or saline plus CCK. Participants will then be given a meal of macaroni and beef. They will be alone in the room while eating, but will be monitored by TV camera. Nothing, however, will be taped or recorded. A tape recording will be used to instruct participants when to begin eating. Participants will be instructed to either eat until an assistant returns to the room, or eat as much as they can. Participants will also fill out questionnaires before and after each meal, and sometimes during a meal. The amount of food consumed after an infusion with CCK will be assessed upon study completion.

Inclusion Criteria:

• Meets DSM-IV criteria for BN
• BN duration of more than 1 year
• Self-induces vomiting
• Weighs between 80 and 120% of ideal body weight

Exclusion Criteria:

• Significant medical illness
• Current or lifetime history of schizophrenia, bipolar disorder, or other psychotic disorder, as defined by DSM-IV-TR criteria
• Current DSM-IV-TR diagnosis of organic mental disorder, factitious disorder, or malingering
• History of a personality disorder (e.g., schizotypal, borderline, or antisocial) that might interfere with the study procedures
• At risk for suicide, as defined by the expression of an imminent plan or attempt within the 6 months prior to study entry
• Currently taking psychotropic medications or medications that affect gastrointestinal function
• Moderate to severe depression, as defined by a score of greater than 28 on the Hamilton Depression Rating Scale
• Drug or alcohol abuse within the 3 months prior to study entry
• Pregnant, planning to become pregnant, or lactating
• Body mass index (BMI) of less than 18 (underweight)