This phase III trial studies how well domperidone works in treating patients with gastrointestinal disorders. Domperidone may help control chronic gastrointestinal disorders and their symptoms, such as pain, bloating, and nausea and vomiting, by stimulating contraction of the stomach to increase its ability to empty itself of food.

PRIMARY OBJECTIVES:

I. To provide treatment with domperidone to patients >= 16 years of age where, according to the investigators' judgment, a prokinetic effect is needed for the relief of gastrointestinal (GI) motility disorders.

OUTLINE:

Patients receive domperidone orally (PO) thrice daily (TID) or four times daily (QID). Treatment continues in the absence of disease progression or unacceptable toxicity.

After completion of study treatment, patients are followed up for at least 30 days.

Inclusion Criteria:

• Patients with GI disorders who have failed standard therapy
• Symptoms or manifestations of: a) gastroparesis; b) refractory gastroesophageal reflux disease (GERD) including persistent esophagitis, refractory heartburn, reflux-related laryngitis, and respiratory symptoms; or c) severe dyspepsia
• Completion of a comprehensive evaluation, including clinical history and physical examination, to eliminate other causes of their symptoms
• Patient has signed the informed consent document agreeing to the use of the study drug, domperidone
• White blood cell (WBC) with differential greater than 3,000/ml
• Alkaline phosphatase less than 1.5 x upper limit of normal
• Alanine aminotransferase (ALT) less than 2 x upper limit of normal
• Aspartate aminotransferase (AST) less than 2 x upper limit of normal
• Bilirubin less than or equal to 2 x upper limit of normal
• Blood urea nitrogen (BUN) less than 2 x upper limit of normal
• Creatinine less than 1.5 x upper limit of normal
• Stable hemoglobin greater than or equal to 8.0 g/dl
• Potassium between range of 3.0 to 5.5
• Magnesium level between 1.6-2.6 mg

Exclusion Criteria:

• Patients with the following cardiac diagnoses: ventricular tachycardia or fibrillation; Torsade des Pointes; clinically significant bradycardia; sinus node dysfunction; heart block; prolonged QTc interval (QTc > 450 milliseconds for males, QTc > 470 milliseconds for females); prior specific cardiovascular conditions of clinically significant valvular heart disease requiring medication, ischemic, or pulmonary heart disease; cardiomyopathy; history of heart failure
• Patients who are receiving antiarrhythmic medications with action on repolarization times (with prolongation of the QTc interval such as amiodarone, disopyramide, dofetilide, flecainide, ibutilide, quinidine, sotalol, dronedarone etc.)
• Patients who are receiving monoamine oxidase (MAO) inhibitors
• Patients with a history of or active liver failure
• Clinically significant electrolyte disorders including sodium < 130 or > 145 and/or potassium < 3.0 or > 5.5 and/or magnesium < 1.6 or > 2.6
• GI hemorrhage or obstruction experienced within the previous 6 weeks
• Presence of a prolactinoma (prolactin-releasing pituitary tumor)
• Pregnant or breast-feeding female (women of childbearing potential [WOCBP], defined as not post-menopausal for 12 months or without previous surgical sterilization, must have a negative urine pregnancy test within 30 days of the first administration of domperidone and must either commit to continued abstinence from heterosexual intercourse or use an effective method of birth control during the course of the study)
• Known allergy to domperidone