Patients with IBS often report pain ______ the abdomen and alternating diarrhea ______ constipation.

Chronic gastritis often develops when the ______ and ______ of the stomach lining are damaged repeatedly due to infections or medications.

Alcohol should be avoided ______ gastritis patients because it irritates the lining ______ the stomach.

Gastroesophageal reflux occurs ______ weakened lower esophageal sphincter and leads ______ heartburn.

Helicobacter pylori colonizes the mucosa ______ the stomach and may persist ______ years if untreated.