Abdominal Pain / Bloating
Symptoms, Causes & Treatment
Abdominal pain and bloating are among the most common reasons for GP consultation. Most causes are benign — IBS, food intolerances, and functional dyspepsia account for the majority — but red flag features always require prompt investigation.
What are Abdominal Pain & Bloating?
Abdominal pain and bloating encompass a wide spectrum from mild functional symptoms to surgical emergencies. The location, character, timing, and associated features of pain guide diagnosis. Most chronic abdominal pain in adults is functional — caused by IBS, FODMAP intolerance, or dyspepsia — but serious conditions including IBD, coeliac disease, ovarian pathology, and malignancy must be excluded before functional diagnoses are made.
Symptoms of Abdominal Pain & Bloating
Abdominal symptoms vary widely. Location, character, timing, and associated features all help identify the cause.
Generalised or localised abdominal pain · Bloating and abdominal distension · Cramping or colicky pain · Pain worse after eating · Excessive wind or belching · Nausea · Change in bowel habit alongside pain or bloating
Severe sudden-onset abdominal pain (peritonitis — call 999) · Pain with fever, vomiting, and rigid abdomen · Rectal bleeding with abdominal pain · Unexplained weight loss with abdominal symptoms · Persistent pain lasting more than 4 weeks in adults over 50
Sudden severe abdominal pain with rigid abdomen · Rectal bleeding with pain · Fever with severe abdominal pain · Unexplained weight loss — seek emergency care immediately.
What Causes Abdominal Pain & Bloating?
Abdominal pain and bloating arise from multiple causes. Most are benign and functional, but serious pathology must always be excluded.
Irritable bowel syndrome is the most common GI cause of bloating and abdominal pain, affecting 10–20% of adults. It involves gut hypersensitivity, dysmotility, and gut-brain axis dysfunction. Bloating is mediated by visceral hypersensitivity rather than actual excess gas.
Small intestinal bacterial overgrowth (SIBO) causes bloating, excessive wind, and diarrhoea from abnormal bacterial fermentation in the small intestine. Common in IBS, coeliac disease, and after bowel surgery. Treated with rifaximin or rotating antibiotics.
Intolerance to lactose (milk sugar), fructose, sorbitol, or FODMAPs causes bloating, cramping, and diarrhoea through osmotic effects and bacterial fermentation. A low-FODMAP diet reduces symptoms in 75% of IBS-type bloating cases.
Appendicitis causes periumbilical pain migrating to the right iliac fossa, with fever, nausea, and rebound tenderness. It is a surgical emergency — any new severe right-sided abdominal pain requires same-day assessment.
Functional dyspepsia causes recurrent upper abdominal discomfort, early satiety, postprandial fullness, and bloating without an organic cause. H. pylori infection, NSAIDs, and stress are contributory factors. Treatment includes H. pylori eradication, PPIs, and low-dose tricyclics.
Inflammatory bowel disease (Crohn’s disease and ulcerative colitis) causes abdominal pain, bloody diarrhoea, weight loss, and fatigue. Early diagnosis with colonoscopy and calprotectin testing prevents disease progression and complications.
Key Risk Factors
Diagnosing Abdominal Pain & Bloating
Stool calprotectin, coeliac antibodies, and basic blood tests form the initial investigation. Red flag features prompt urgent imaging and endoscopy.
Treatment for Abdominal Pain & Bloating
Treatment targets the underlying cause. Functional conditions are managed with dietary modification, antispasmodics, and gut-directed therapy.
Supportive Measures
Apply a warm heat pack to the abdomen for comfort. Eat small frequent meals. Stay well hydrated. Keep a food and symptom diary. Reduce stress. Peppermint tea may relieve bloating. Antispasmodics (mebeverine) and antacids (Gaviscon) provide symptomatic relief.
Long-Term Management
IBS, functional dyspepsia, and IBD all require ongoing long-term management. Annual GP review, dietitian input, and psychological support improve long-term outcomes. Red flag symptoms developing in a known IBS patient still require prompt investigation.
When to Seek Help
Sudden severe abdominal pain with rigidity, guarding, fever, or vomiting — call 999 immediately. This may indicate peritonitis, appendicitis, or perforation.
See a GP if abdominal symptoms are new, worsening, or accompanied by red flag features. An online consultation is a good first step for non-emergency abdominal symptoms.
Preventing Abdominal Symptoms
Many GI conditions are preventable through diet, exercise, hydration, and stress management.
Eat regular small meals rather than large ones. Avoid eating too quickly. Chew food thoroughly. Limit gas-producing foods (beans, pulses, cruciferous vegetables) and carbonated drinks to reduce bloating.
Maintain a high-fibre diet (25–30g per day) from whole grains, vegetables, fruits, and legumes. Adequate dietary fibre prevents constipation, reduces bloating, and protects against colorectal cancer.
Drink 1.5–2 litres of fluid daily (mostly water). Adequate hydration prevents constipation, reduces kidney stone risk, and supports healthy bowel transit.
Regular aerobic exercise promotes bowel motility, reduces bloating, and significantly lowers colorectal cancer risk. Aim for 150 minutes of moderate activity per week.
Attend NHS bowel cancer screening at age 50+ (FIT test). Screening colonoscopy for those with a family history of colorectal cancer. Early detection saves lives.
Manage stress through mindfulness, CBT, relaxation techniques, and exercise. The gut-brain axis means that psychological stress directly worsens GI symptoms including bloating, IBS, and dyspepsia.
Getting Treatment
A GP can assess abdominal symptoms, arrange investigations, and diagnose functional conditions including IBS and food intolerances. Red flag features require urgent referral.
Expert clinical advice, when you need it.
Abdominal Pain & Bloating — Frequently Asked Questions
Abdominal bloating most commonly results from IBS, food intolerances (lactose, FODMAPs), swallowing excess air, constipation, or functional dyspepsia. Less commonly, it may indicate coeliac disease, small intestinal bacterial overgrowth (SIBO), or ovarian pathology in women. A GP assessment with stool calprotectin, coeliac antibodies, and basic blood tests can identify the cause.
See a GP urgently if abdominal pain is severe, sudden in onset, accompanied by fever and vomiting, or associated with rectal bleeding or unexplained weight loss. Sudden severe abdominal pain with a rigid abdomen may indicate peritonitis, appendicitis, or bowel perforation — call 999 immediately.
The low-FODMAP diet eliminates fermentable carbohydrates (Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols) for 6–8 weeks, then systematically reintroduces them to identify personal triggers. Around 75% of IBS patients respond. It should be supervised by a dietitian to ensure nutritional adequacy.
Yes. Stress, anxiety, and depression all worsen abdominal pain and bloating through the gut-brain axis. Psychological stress alters gut motility, increases visceral sensitivity, and changes gut microbiome composition. Addressing mental health is central to managing functional abdominal symptoms.
H. pylori is a common bacterial infection of the stomach lining that causes peptic ulcers and chronic gastritis. It is diagnosed by urea breath test, stool antigen test, or gastric biopsy. Treatment with 7-day triple therapy (PPI + two antibiotics) eradicates the infection in over 90% of cases.
See a GP if you have new bowel symptoms after age 50, unexplained weight loss with abdominal pain, rectal bleeding, or a family history of colorectal cancer. These are red flag features requiring colonoscopy to exclude serious pathology before attributing symptoms to a functional cause.
An online or in-person GP can assess abdominal symptoms, arrange stool calprotectin, coeliac antibodies, blood tests, and ultrasound. IBS, functional dyspepsia, and food intolerances can be diagnosed and managed in primary care. Complex or red flag presentations are referred for gastroenterology assessment.
No. Bloating from IBS or food intolerance is not caused by excess gas in most people, but by visceral hypersensitivity — the gut feels bloated even when gas levels are normal. This is why antiflatulence remedies are often unhelpful, and treatments targeting gut sensitivity (low-FODMAP diet, antispasmodics) work better.