The digestive system includes the gastrointestinal tract, liver, pancreas and gallbladder. It breaks food down, absorbs nutrients and water, and removes waste. Use the links below to read about common digestive symptoms and conditions.
Common digestive conditions
- Heartburn and Acid Reflux (GERD) — reflux of stomach contents that may cause heartburn and regurgitation.
- Gastritis — inflammation of the stomach lining.
- Peptic Ulcer — an ulcer in the stomach or upper small intestine.
- Irritable Bowel Syndrome (IBS) — recurring abdominal pain associated with changes in bowel movements.
- Crohn’s Disease — chronic inflammation that can affect different parts of the digestive tract.
- Ulcerative Colitis — chronic inflammation and ulcers affecting the colon and rectum.
- Diverticulosis and Diverticulitis — pouches in the colon that may sometimes become inflamed or bleed.
- Celiac Disease — an immune-mediated condition in which gluten damages the small intestine.
- Lactose Intolerance — difficulty digesting lactose that may cause gas, bloating and diarrhea.
- Appendicitis — inflammation of the appendix that usually requires urgent assessment.
- Acute Cholecystitis — inflammation of the gallbladder, often related to gallstones.
- Infant Colic — repeated prolonged crying in an otherwise healthy young infant.
Common bowel symptoms
- Constipation — difficult, infrequent or incomplete bowel movements.
- Diarrhea — loose or watery stools with many possible causes.
- Bloating and Gas — abdominal fullness, distension or intestinal gas.
- Hemorrhoids — swollen veins in or around the anus and lower rectum.
When to seek emergency help
Seek emergency care for sudden or severe abdominal pain, a rigid or very tender abdomen, vomiting blood or material resembling coffee grounds, black tarry stool, heavy rectal bleeding, collapse, severe breathing difficulty, or inability to pass stool or gas with pain and vomiting.
Testing and treatment
Depending on symptoms, assessment may include blood or stool tests, testing for infection or inflammation, imaging, endoscopy or colonoscopy. Treatment depends on the diagnosis and may involve hydration, dietary changes, medicines or a procedure. Do not begin a gluten-free diet before testing for celiac disease unless a qualified clinician advises it, because removing gluten may make diagnostic tests less accurate.
Sources and further reading
Last reviewed: 4 September 2026. This page provides general health information and does not replace individual medical or dietary advice.