Continuous Glucose Monitoring and Insulin Pump Therapy in Diabetic Gastroparesis

Inclusion Criteria: * Age 18 - 70 years old at registration * Type 1 or Type 2 diabetes mellitus for at least 2 years * Symptoms of gastroparesis (nausea, vomiting, early satiety, bloating, fullness, discomfort) for at least 1 year prior to registration * Gastroparesis Cardinal Symptom Index (GCSI) score of 18 * Delayed gastric emptying on gastric scintigraphy within 1 year of registration, defined as greater than 60% retention at 2 hours or greater than 10% retention at 4 hours * Hemoglobin A1c of at least 8.0% at registration regardless of current therapy. Individuals already receiving diabetes therapy via an insulin pump will be eligible for study participation if, in the opinion of the investigators, he/she may acquire additional benefit from continuous glucose monitoring that might improve glycemic control * Normal upper endoscopy within 1 year of registration * No clinical or imaging evidence of obstruction * Successful mastering of use of CGMS during the run-in period Exclusion Criteria: * Prior gastric surgery including fundoplication * Other systemic disease potentially causative of gastrointestinal symptoms * Acute or chronic renal insufficiency with creatinine \>1.5 mg/dL * Psychiatric disease or eating disorder * Pregnancy * Any other condition which, in the opinion of the investigators, would impede compliance or hinder completion of the study