Evaluation and Management of Generalized Abdominal Pain and Bloatedness
Begin with a targeted history focusing on alarm symptoms, followed by selective laboratory testing only when indicated—extensive imaging and endoscopy are unnecessary without red flags. 1
Initial Clinical Assessment
Your first priority is identifying alarm features that mandate immediate investigation:
- Weight loss >10% suggests malabsorption, malignancy, or serious underlying disease 2, 1
- Gastrointestinal bleeding (visible blood or melena) requires urgent evaluation 1
- Persistent or severe vomiting may indicate gastroparesis or obstruction 2, 1
- Iron-deficiency anemia warrants celiac disease testing and possible endoscopy 1
- Family history of inflammatory bowel disease or colorectal cancer increases risk 1
- Women ≥50 years with new-onset bloating require evaluation for ovarian cancer, as bloating and abdominal fullness are often presenting symptoms in this population 2, 1
Characterize the Symptom Pattern
Assess the relationship to meals and specific foods (lactose, fructose, gluten) to identify potential dietary triggers 1, 3. Evaluate bowel habits using the Bristol Stool Scale to identify constipation, diarrhea, or alternating patterns suggesting IBS 1.
Critical defecation details to elicit: straining with soft stool, need for digital disimpaction or splinting, incomplete evacuation sensation, or fecal incontinence—these suggest pelvic floor dyssynergia, not simple constipation 2, 1. A digital rectal examination helps identify increased or decreased sphincter tone, pelvic floor dyssynergia, rectal prolapse, anal stricture, or rectocele 2.
Laboratory Testing Strategy
Order tissue transglutaminase IgA with total IgA levels for patients with IBS-diarrhea or alarm symptoms to screen for celiac disease. 2, 1 This is the recommended serologic reference standard, with small bowel biopsy confirming diagnosis if serology is positive 2.
Complete blood count and comprehensive metabolic profile are only recommended when alarm symptoms are present or systemic disease is suspected 1. An abdominal X-ray (KUB) may be useful when severe constipation is suspected to reveal increased stool burden 2, 1.
Imaging and Endoscopy—When to Use
Reserve abdominal imaging and upper endoscopy exclusively for patients with alarm features, recent worsening of symptoms, or abnormal physical examination findings. 4 In the absence of alarm symptoms, the yield of clinically meaningful findings is extremely low 2, 4.
Consider upper endoscopy in patients >40 years with dyspeptic symptoms and bloating, particularly in geographic regions with high Helicobacter pylori prevalence 2. CT/MRI is not routinely recommended without alarm symptoms 2.
Motility Studies—A Common Pitfall
Do NOT order gastric emptying studies routinely for bloating and distention alone. 4 Approximately 40% of patients with gastroparesis report bloating that correlates with nausea, abdominal fullness, and abdominal pain, but none of these symptoms correlate with the degree of gastric emptying delay per scintigraphy 2. Consider gastric scintigraphy only when nausea and vomiting are prominent symptoms or in patients with severe refractory upper GI symptoms combined with weight loss 2, 4.
Constipation-Predominant Symptoms
If constipation is present, use Rome IV criteria to diagnose IBS-C or chronic constipation 2. For women with IBS-C not responding to standard therapies or those with suspected pelvic floor disorders based on history or examination findings, anorectal physiology testing combined with balloon expulsion is advocated 2. Defecography with barium or MRI can be done if there is concern for structural etiology such as pelvic organ prolapse or rectal intussusception 2.
Initial Management Approach
Start with a short-term elimination diet to identify and restrict potential dietary triggers—this is the simplest and most cost-effective approach. 1, 4 A low-FODMAP diet may be considered for suspected carbohydrate intolerance 2, 1. Reserve hydrogen/methane breath testing for patients who fail dietary restriction trials, including testing for lactose, fructose, or sucrose intolerance 2, 4.
For patients with self-reported gluten sensitivity, fructans in gluten-rich foods rather than gluten may cause symptoms, so elimination of fructans only is recommended 2, 1. A dietitian consultation is recommended when dietary modifications are needed to avoid malnutrition from prolonged restrictions 1.
Pharmacologic Options
Secretagogues (linaclotide and lubiprostone) show superiority over placebo for abdominal bloating in constipation. 1 Central neuromodulators such as tricyclic antidepressants and serotonin-norepinephrine reuptake inhibitors may help manage hypersensitivity-related bloating 1.
For patients at high risk of SIBO (chronic watery diarrhea, malnutrition, weight loss, or systemic diseases causing dysmotility like cystic fibrosis or Parkinson disease), rifaximin is effective for SIBO-related bloating, though it is not FDA-approved for this indication 2, 1. Patients with these risk factors may need diagnostic testing or empiric treatment with antibiotics 2.
Special Considerations
Fecal elastase may be considered in patients with bloating and pain despite adequate pancreatic enzyme replacement, suggesting chronic pancreatitis 2, 1. Severe constipation is present in >30% of patients with symptoms of severe gastroparesis and is associated with delayed small bowel and colonic transit 2.
Diaphragmatic breathing, central neuromodulators, and brain-gut behavioral therapies may be considered for treatment regardless of diagnostic correlates 2.