Causes of severe stomach bloating

Bloating may feel like pressure, fullness, or visible abdominal enlargement. Gas can build up when digestion produces more air than usual or when swallowed air moves slowly. Lactose intolerance and other food intolerance can cause bloating after particular foods, often with cramps or loose stools. Coeliac disease can damage the small bowel after gluten exposure and may cause ongoing digestive symptoms. Irritable bowel syndrome can combine bloating with abdominal pain and changes in bowel habit.

Giardiasis and Helicobacter pylori infection can disturb digestion in different ways. Constipation, a large meal, and hormonal changes are also possible contributors. The pattern matters: symptoms after a food, overnight changes, diarrhoea, weight loss, vomiting, or blood in stool each alter the need for assessment.

Eat slowly, chew well, drink regularly, and keep a diary of foods, bowel movements, pain, and bloating. Gentle movement may help gas pass. Avoid removing several food groups without professional guidance, because this can make the diet inadequate and may interfere with coeliac testing. A clinician or nutrition counsellor can help identify a safe, structured approach. Do not start a gluten-free diet before discussing coeliac testing if that condition is being considered.

Get urgent help for severe or rapidly worsening pain, repeated vomiting, a swollen rigid abdomen, inability to pass stool or gas, fainting, fever with marked illness, or blood in vomit or stool. Arrange medical review for persistent bloating, unintentional weight loss, ongoing diarrhoea, anaemia symptoms, or a new change in bowel habit. These patterns need a clinical explanation rather than prolonged dietary restriction.

Ask whether your pattern suggests intolerance, coeliac disease, irritable bowel syndrome, constipation, or infection. Ask which tests should come before dietary changes, how to keep nutrition adequate, and whether a referral to nutrition counselling would help.