What are the management options for Irritable Bowel Syndrome (IBS)?

Management of Irritable Bowel Syndrome (IBS)

For all patients with IBS, begin with lifestyle modifications and dietary interventions as first-line therapy, escalating to pharmacological treatments based on predominant symptom pattern (diarrhea, constipation, or pain), and reserve psychological therapies for moderate-to-severe or refractory cases. 1, 2

Initial Assessment and Patient Education

• Provide clear explanation that IBS is a disorder of gut-brain interaction with a benign but relapsing/remitting course to establish realistic expectations and reduce anxiety 1, 2
• Listen to patient concerns and identify their beliefs about the condition, addressing fears directly rather than ordering extensive testing once diagnosis is established 1, 2
• Avoid extensive testing in patients under 45 years without alarm features (unintentional weight loss ≥5%, blood in stool, fever, anemia, family history of colon cancer or inflammatory bowel disease) 1
• Consider serological testing to exclude celiac disease, but do not routinely test for C-reactive protein, fecal calprotectin, or IgG-based food allergy testing 3, 1

First-Line: Lifestyle Modifications (For All Patients)

• Recommend regular physical activity to all patients, as exercise provides significant benefits for symptom management 1, 2
• Promote patient empowerment through self-management education using handouts, self-help books, websites, and apps targeting physical activity, sleep hygiene, mindful eating, and assertive communication 2, 4
• Advise balanced diet with adequate fiber intake, regular time for defecation, and proper sleep hygiene 1

Dietary Interventions (Symptom-Driven Approach)

General Dietary Modifications

• Start with soluble fiber supplementation (ispaghula/psyllium) at low doses (3-4 g/day) and gradually increase for constipation-predominant IBS (IBS-C) 1, 2
• Avoid insoluble fiber (wheat bran) as it may worsen symptoms, particularly bloating 1, 2
• Identify and reduce excessive intake of lactose, fructose, sorbitol, caffeine, or alcohol for diarrhea-predominant IBS (IBS-D) 2

Low FODMAP Diet (For Persistent Symptoms)

• Refer to a trained dietitian for a supervised trial of low FODMAP diet delivered in three phases: restriction, reintroduction, and personalization 1, 2, 5
• This approach should be considered for individuals with moderate to severe gastrointestinal symptoms in the absence of red flags (eating pathology or severe mental illness) 4
• For patients with co-occurring moderate-to-severe anxiety or depression, consider a gentle FODMAP diet or Mediterranean diet instead 4

When to Refer to a Dietitian

• Patient reports considerable intake of foods that trigger IBS symptoms 4
• Patient requests or is receptive to dietary modification advice 4
• Dietary deficits or nutrition red flags are present (avoidance of multiple food groups, unintentional weight loss ≥5% in previous 6 months, or nutrient deficiency) 4
• Food-related fear is pathological 4

Pharmacological Treatment (Symptom-Pattern Specific)

For Abdominal Pain and Cramping

• Use antispasmodics (anticholinergic agents like dicyclomine) as first-line therapy for abdominal pain, particularly when symptoms are meal-related 1, 2
• Consider peppermint oil as an alternative antispasmodic, though evidence is more limited 1, 2, 6

For Diarrhea-Predominant IBS (IBS-D)

• Prescribe loperamide 4-12 mg daily (either regularly or prophylactically before going out) as first-line therapy to reduce stool frequency, urgency, and fecal soiling 1, 2
• Consider eluxadoline for adults with IBS-D as an FDA-approved option 7, 3
• Alosetron may be used in women with severe IBS-D, but be aware of serious risks including ischemic colitis and complications of constipation (29% constipation rate, 11% withdrawal rate due to constipation) 8
• Consider testing for bile acid malabsorption; cholestyramine may benefit this subset but is often less well tolerated than loperamide 2, 9

For Constipation-Predominant IBS (IBS-C)

• Increase dietary fiber or use soluble fiber supplements like ispaghula/psyllium 2
• Consider FDA-approved agents like lubiprostone or linaclotide for refractory cases 3

For Mixed IBS (IBS-M) or Refractory Pain

• Prescribe tricyclic antidepressants (TCAs) as the most effective first-line pharmacological treatment, starting with amitriptyline 10 mg once daily and titrating to 30-50 mg once daily 1, 2
• Low-dose TCAs are preferred for gastrointestinal symptoms, particularly pain, but may aggravate constipation 2
• If concurrent mood disorder is present, use a selective serotonin reuptake inhibitor (SSRI) instead, as low-dose TCAs are unlikely to address psychological symptoms 2
• Continue TCAs for at least 6 months if patient reports symptomatic improvement 2

For Bloating

• Trial probiotics for 12 weeks for global symptoms and bloating; discontinue if no improvement 1, 2
• Consider reducing intake of fiber, lactose, or fructose as relevant 2

Psychological Therapies (For Moderate-to-Severe or Refractory Cases)

• Consider IBS-specific cognitive behavioral therapy or gut-directed hypnotherapy when symptoms persist despite pharmacological treatment for 12 months 1, 2, 5
• These brain-gut behavior therapies are specifically designed for IBS and differ from psychological therapies that target depression and anxiety alone 2, 4
• Become familiar with the indications for brain-gut behavior therapies and the differences between these and psychological therapies specifically for depression and anxiety 4

When to Refer to a Gastropsychologist

• IBS symptoms or their impact are moderate to severe 4, 2
• Patient accepts that symptoms are related to gut-brain dysregulation 4, 2
• Patient has time to devote to learning new coping strategies 4, 2

Multidisciplinary Care Coordination

• Build collaborative links with gastroenterology dietitians and gastropsychologists to coordinate high-quality care 2, 4
• An integrated care approach that addresses gastrointestinal symptoms with nutrition and brain-gut behavior therapies is considered the gold standard 4, 5
• Assure patients that you will remain involved in their care and work with their other practitioners to ensure holistic treatment 4

Treatment Monitoring and Adjustment

• Review treatment efficacy after 3 months and discontinue ineffective medications 2
• Recognize that symptoms may relapse and remit over time, requiring periodic adjustment of treatment strategy 2
• For probiotics, recommend a 12-week trial and discontinue if no improvement 1, 2

Critical Pitfalls to Avoid

• Do not pursue extensive testing once IBS diagnosis is established in patients under 45 without alarm features 1, 2
• Do not recommend IgG-based food allergy testing, as true food allergy is rare in IBS 1
• Do not use wheat bran or insoluble fiber, as it may worsen bloating 1, 2
• Do not recommend osmotic laxatives for overall IBS symptoms 3
• For patients with psychological-predominant symptoms, consider a Mediterranean diet rather than aggressive FODMAP restriction 4