Inclusion Criteria:  All patients between 8 and 18 years-old, based on Rome IV criteria that provide evidence-based definitions and classifications for so-called functional gastrointestinal disorders, such as functional dyspepsia in children and adolescents, with 1 or more of the following bothersome symptoms at least 4 days per month for at least 2 months: Postprandial fullness Early satiation Epigastric pain or burning not associated with defecation After appropriate evaluation, the symptoms cannot be fully explained by another medical condition Postprandial distress syndrome includes bothersome postprandial fullness or early satiation that prevents finishing a regular meal. Supportive features include upper abdominal bloating, postprandial nausea, or excessive belching. Epigastric pain syndrome, which includes all of the following: bothersome (severe enough to interfere with normal activities) pain or burning localized to the epigastrium. The pain is not generalized or localized to other abdominal or chest regions and is not relieved by defecation or passage of flatus. Supportive criteria can include (a) burning quality of the pain but without a retrosternal component and (b) the pain commonly induced or relieved by ingestion of a meal but may occur while fasting.  Exclusion Criteria:  The presence of alarm symptoms and signs which might suggest underlying organic pathology as listed in Rome III criteria including: (Persistent right upper or right lower quadrant pain, dysphagia, persistent vomiting, gastrointestinal blood loss, nocturnal diarrhea, family history of inflammatory bowel disease, celiac disease, or peptic ulcer disease, pain that wakes the child from sleep, arthritis, perirectal disease, involuntary weight loss, deceleration of linear growth, delayed puberty or unexplained fever). Gastrointestinal tract surgery, one year post-operative. Diabetes mellitus Any debilitating disorder e.g. malignancy, severe malnutrition, renal failure, etc. Patients on medications that may produce GIT disorders e.g. aspirin, steroids or NSAIDs