What are the steps to treat irritable bowel syndrome (IBS)?

Step-by-Step Treatment of Irritable Bowel Syndrome

The treatment of irritable bowel syndrome should follow a structured approach beginning with making a positive diagnosis, providing education and reassurance, implementing dietary modifications, adding psychological therapies when needed, and using targeted pharmacological interventions for specific symptoms. 1, 2

Step 1: Make a Positive Diagnosis

• For patients <45 years meeting three or more IBS criteria without alarm symptoms, make a confident diagnosis without extensive testing 1
• Limited investigations (e.g., coeliac serology) may be needed, but avoid exhaustive testing 1
• Early diagnosis facilitates prompt treatment initiation and access to integrated management 1

Step 2: Listen and Provide Education/Reassurance

• Address patient concerns and identify beliefs; a symptom diary may be helpful 1
• Explain the brain-gut interaction, emphasizing:
  • Benign prognosis with relapsing/remitting course
  • Role of stress in symptom aggravation
  • Concept of sensitive/hyperactive gut 1
• Use patient-friendly language to discuss how depression or anxiety can lead to onset, perpetuation, or maintenance of IBS symptoms 1

Step 3: Implement Dietary Modifications

• Begin with dietary interventions as first-line treatment: 2
  • Establish baseline fiber intake
  • Adjust fiber intake: increase for constipation, decrease for diarrhea 1
  • Consider a low FODMAP diet for moderate to severe symptoms, delivered by a dietitian 1, 2, 3
  • For patients with psychological-predominant symptoms, consider a Mediterranean diet 2, 3
  • Identify and address excessive intake of lactose, fructose, sorbitol, caffeine, or alcohol 1
  • Consider trial of lactose/fructose exclusion if appropriate 1, 2

Step 4: Recommend Lifestyle Modifications

• Promote balanced diet with adequate fiber intake
• Encourage regular exercise
• Establish regular time for defecation 1
• Implement sleep hygiene improvements 2
• Consider mindful eating practices 2

Step 5: Add Targeted Pharmacological Treatment

For specific symptoms, add medications as needed:

• Abdominal pain:

  • First-line: Antispasmodics (dicyclomine) 1, 2
  • Second-line: Tricyclic antidepressants (amitriptyline 10-50mg at bedtime) for pain with sleep disturbance 1, 2

• Diarrhea:

  • Loperamide 4-12mg daily (regularly or prophylactically) 1, 2
  • Consider cholestyramine for a small subset of patients 1

• Constipation:

  • Increase dietary fiber (bran) 1
  • If symptoms worsen, try ispaghula/psyllium 1
  • For IBS-C: Consider lubiprostone 8mcg twice daily 4

• Bloating:

  • Reduce intake of fiber/lactose/fructose as relevant 1
  • Consider peppermint oil as an adjunctive treatment 5

Step 6: Incorporate Psychological Therapies

For patients with persistent symptoms or psychological comorbidities:

• Begin with explanation and reassurance 1
• Trial simple relaxation therapy 1
• Consider more advanced therapies when available:
  • Cognitive behavioral therapy for recognizing maladaptive patterns 2
  • Gut-directed hypnotherapy, especially for younger patients without serious psychopathology 1, 2
  • Mindfulness-based stress reduction 1, 2

Step 7: Consider Specialist Referrals

• Gastroenterologist: When diagnosis is uncertain or symptoms are severe/refractory to first-line treatments 2
• Specialist dietitian: For patients with high intake of trigger foods, dietary deficits, or food-related fear 2
• Psychologist/Psychiatrist: For moderate to severe depression/anxiety, suicidal ideation, or impaired quality of life 1, 2

Common Pitfalls and Caveats

• Avoid exhaustive investigations that can reinforce illness behavior 1
• Don't neglect psychological aspects of IBS, as they significantly impact symptom severity and quality of life 1
• Be cautious with restrictive diets in patients with eating disorder risk 6
• Review treatment efficacy after 3 months and discontinue ineffective interventions 2
• Avoid opioid analgesics for chronic abdominal pain as they can worsen GI dysmotility 2
• Monitor for serious complications of medications:
  • Alosetron: risk of ischemic colitis and severe constipation 7
  • Lubiprostone: nausea, diarrhea, syncope, and hypotension 4

By following this structured approach and tailoring interventions to predominant symptoms, most patients with IBS can achieve significant symptom improvement and enhanced quality of life.