Fuctional dyspepsia is defined as the presence of symptoms thought to originate from the gastroduodenum, in the absence of any structural or metabolic disease that is likely to explain these symptoms. To facilitate its diagnostic and therapeutic approach, the Rome consensus proposed to distinguish 2 subgroups: postprandial distress syndrome (PDS), is characterized by meal-related symptoms such as early satiation and postprandial fullness. At present, no validated instrument is available for the assessment of the symptom responsiveness in patients suffering from PDS. To develop a new PRO questionnaire, we have previously conducted focus group sessions and cognitive interviews in PDS patients to identify all relevant symptom items that characterize PDS. In this study we aim to validate the provisional Leuven Postprandial Distress Scale (LPDS) through the assessment of its consistency, reliability and ability to detect change in the framework of a controlled treatment trial.

Inclusion Criteria:

• Patients with PDS diagnosis as per Rome III by Rome III questionnaire (see appendix 1B)
• Patients must provide witnessed written informed consent prior to any study procedures being performed
• Patients aged between 18 and 70 years inclusive
• Male or female patients
• Patients who are capable to understand the study and the questionnaires, and to comply with the study requirements

Exclusion Criteria:

• Patients with any condition which, in the opinion of the investigator, makes the patient unsuitable for entry into the study
• Patients with an active major psychiatric condition (depression, anxiety disorder, alcohol or substance abuse). Patients who are taking a stable dose of a single antidepressant (with the exception of amitryptiline) during the last 3 months are eligible.
• Females who are pregnant or lactating.
• Patients who are H. Pylori positive or patients who received treatment for HP eradication during the last 3 months.
• Patients suffering from diabetes type 1 or type 2.
• Patients taking medication for functional dyspepsia will need a wash-out period of 2 weeks before they can be screened
• Patients with known hypersensitivity to gastroprokinetic drugs.
• Patients with confirmed gastro-intestinal disease.
• Patients with former digestive surgery affecting upper gut motility.
• Patients affected by concomitant disease responsible for digestive symptoms
• Patients presenting with predominant symptoms of irritable bowel syndrome (IBS)
• Patients presenting symptoms of EPS several times a week according to Rome III questionnaire
• Patients presenting daily symptoms of CIN on Rome III questionnaire
• Patients presenting vomiting more than one day a month.
• Patients presenting daily symptoms of Excessive belching according to Rome III questionnaire
• Patients presenting predominant GERD according to GERD questionnaire