What is the best approach to manage a patient with increased bloating, considering potential underlying causes such as gastrointestinal disorders, food intolerances, or hormonal imbalances?

Management of Increased Bloating

Start with a targeted history to identify the underlying mechanism, then proceed with a stepwise diagnostic and treatment approach based on the most likely etiology—dietary modification and constipation management are first-line interventions for most patients without alarm features. 1

Initial Clinical Assessment

Key Historical Features to Elicit

• Relationship to meals and specific foods: Ask specifically about lactose, fructose, gluten, artificial sweeteners (sugar alcohols, sorbitol), and high-FODMAP foods, as fructose intolerance affects 60% and lactose intolerance affects 51% of bloating patients 2

• Bowel movement patterns: Use the Bristol Stool Scale to assess stool consistency, frequency, and whether straining occurs even with soft stool (suggesting pelvic floor dyssynergia) 3

• Associated symptoms: Nausea and vomiting suggest gastroparesis; constipation points to IBS-C or pelvic floor disorder; diarrhea may indicate SIBO or carbohydrate malabsorption 1, 2

• Timing of distension: Worsening after meals with visible abdominal protrusion suggests abdominophrenic dyssynergia 1, 2

Alarm Features Requiring Urgent Evaluation

Order abdominal imaging and upper endoscopy ONLY if alarm features are present 1, 2:

• Weight loss >10% 2
• Gastrointestinal bleeding 3
• Vomiting 3
• Family history of inflammatory bowel disease or colorectal cancer 3
• Recent worsening symptoms or abnormal physical examination 1, 2

Diagnostic Algorithm by Clinical Presentation

If Constipation is Present

• Diagnose using Rome IV criteria for IBS-C or chronic constipation 1
• Perform anorectal manometry (ARM) to rule out pelvic floor dyssynergia, as this is a treatable cause of bloating with constipation 1
• If pelvic floor disorder is identified, biofeedback therapy is effective 1

If Food Intolerance is Suspected

• The simplest and most cost-effective approach is a 2-week dietary restriction trial rather than immediate testing 1
• If symptoms persist despite dietary restriction, consider hydrogen breath testing for lactose, fructose, or sucrose intolerance 1, 2
• Reserve breath testing for patients refractory to dietary modifications 1

If SIBO Risk Factors are Present

SIBO should be considered in high-risk patients with chronic watery diarrhea, malnutrition, weight loss >10%, or systemic diseases causing small bowel dysmotility 2

• Diagnose using hydrogen-based breath testing with glucose or lactulose, or small bowel aspirates 1, 2
• Do not routinely test for SIBO in uncomplicated bloating 1

If Nausea and Vomiting Accompany Bloating

• Gastric emptying studies may be considered to rule out gastroparesis, but should not be ordered routinely for bloating alone 1, 2
• Whole gut motility studies should not be ordered unless additional treatment-refractory lower GI symptoms exist 1

If Visible Abdominal Distension Occurs After Meals

• Consider abdominophrenic dyssynergia (APD), which involves inappropriate diaphragm contraction causing distention not explained by increased intestinal gas 1, 2
• Treat with diaphragmatic breathing exercises and central neuromodulators 1

Treatment Approach

First-Line Dietary Interventions

When dietary modifications are needed (e.g., low-FODMAP diet), a gastroenterology dietitian should preferably monitor treatment 1

• Trial elimination of lactose, fructose, artificial sweeteners, and high-FODMAP foods based on history 1, 2
• Fructans in gluten-containing foods may be the culprit in self-reported gluten sensitivity rather than gluten itself 2

Constipation-Directed Therapy

Medications used to treat constipation should be considered for treating bloating if constipation symptoms are present 1

• Osmotic laxatives and increased fiber are first-line for chronic idiopathic constipation 4

Pharmacologic Options

• Central neuromodulators (antidepressants) reduce visceral hypersensitivity, raise sensation threshold, and improve psychological comorbidities 1
• Proton pump inhibitors for gastric belching related to GERD 1, 2
• Baclofen for excess transient lower esophageal sphincter relaxations causing belching 1
• Probiotics should NOT be used to treat abdominal bloating and distention 1
• Simethicone is FDA-approved for relief of pressure and bloating commonly referred to as gas 5

Behavioral and Psychological Therapies

Psychological therapies such as hypnotherapy, cognitive behavioral therapy, and other brain-gut behavioral therapies may be used to treat patients with bloating and distention 1

• These are particularly effective when visceral hypersensitivity or psychological comorbidities are present 1
• Diaphragmatic breathing is specifically used for abdominophrenic dyssynergia 1

Common Pitfalls to Avoid

• Do not order extensive motility testing routinely—reserve for treatment-refractory cases with additional symptoms 1
• Do not attribute bloating to hormonal imbalances without first excluding gastrointestinal causes 1
• Do not use antibiotics empirically for presumed SIBO without appropriate testing and patient selection, as they are not FDA-approved for this indication and careful selection is needed 1
• Do not delay evaluation if alarm features are present, even in younger patients 2