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

Management of Irritable Bowel Syndrome (IBS)

Begin with a positive clinical diagnosis in patients under 45 years meeting Rome criteria without alarm features (unintentional weight loss ≥5%, blood in stool, fever, anemia, family history of colon cancer or inflammatory bowel disease), and avoid extensive testing once IBS is established. 1, 2

Initial Patient Education and Relationship Building

• Provide clear explanation that IBS is a disorder of gut-brain interaction with a benign but relapsing/remitting course to establish realistic expectations 1, 2
• Listen to patient concerns and identify their specific beliefs about the condition, addressing fears directly rather than ordering more tests 1, 2
• Determine why the patient is seeking care now (cancer phobia, disability concerns, interpersonal distress, or symptom exacerbation) as this guides management 3
• Consider having patients keep a 2-week diary of food intake and gastrointestinal symptoms to identify triggers and engage them in disease management 4, 3
• Adjust visit duration and frequency to accommodate mental health needs, especially if there is history of abuse 4

First-Line Lifestyle Modifications (For All Patients)

• Prescribe regular physical activity to all IBS patients, as exercise provides significant benefits for symptom management 1, 2
• Establish regular time for defecation and ensure adequate sleep hygiene 5, 1
• Promote patient empowerment through education using handouts, self-help books, websites, and apps targeting physical activity, sleep hygiene, mindful eating, and assertive communication 2

Dietary Interventions

Initial Fiber Modification

• For constipation-predominant IBS (IBS-C): Start with soluble fiber supplementation (ispaghula/psyllium) at 3-4 g/day and gradually increase to avoid bloating 5, 1, 2
• Avoid insoluble fiber (wheat bran) as it worsens symptoms, particularly bloating 5, 1
• For diarrhea-predominant IBS (IBS-D): Decrease fiber intake 4, 2

Trigger Food Identification and Elimination

• Identify and reduce excessive intake of lactose, fructose, sorbitol, caffeine, or alcohol for IBS-D 1, 2
• Trial lactose/fructose/alcohol exclusion if appropriate based on diary findings 4
• Reassure that true food allergy is rare (avoid IgG-based food allergy testing) but food intolerance is common 4, 1

Low FODMAP Diet (For Moderate to Severe Symptoms)

• Refer to a trained dietitian for a supervised trial of low FODMAP diet delivered in three phases: restriction, reintroduction, and personalization 1, 2, 6
• Reserve this diet for patients with access to a specialist dietitian to avoid nutritional deficits 4, 2
• This approach is particularly effective but requires professional guidance 2, 7

Pharmacological Treatment by Predominant Symptom

For Abdominal Pain and Cramping

• Use antispasmodics with anticholinergic properties (dicyclomine) as first-line therapy for abdominal pain, particularly when symptoms are meal-related 5, 1, 2
• Administer before meals for patients with daily symptoms, especially postprandial 3
• For infrequent but severe episodes, sublingual hyoscyamine produces rapid relief 3
• Peppermint oil may be useful as an alternative antispasmodic 5, 1, 7

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, 8
• Use in divided doses, typically morning dose before breakfast (2-6 mg) and possibly later in the day when symptoms are prominent 3
• Encourage patients to make decisions about when and how much to use, especially in anticipation of diarrhea when engaged in activities outside the home 3
• Codeine 30-60 mg, 1-3 times daily can be tried but central nervous system effects often limit use 4, 2
• Cholestyramine may benefit a small subset with bile acid malabsorption but is often less well tolerated than loperamide 2, 8

For Constipation-Predominant IBS (IBS-C)

• Increase dietary fiber or use soluble fiber supplements like ispaghula/psyllium as described above 1, 2
• For IBS-C refractory to fiber: Consider linaclotide 290 mcg once daily, which demonstrated statistically significant improvement in combined responder rates (abdominal pain reduction ≥30% plus ≥3 complete spontaneous bowel movements with increase ≥1 from baseline) in two large randomized controlled trials 9, 7

For Bloating

• Try reducing intake of fiber/lactose/fructose as relevant 4, 2
• Trial probiotics for 12 weeks for global symptoms and bloating; discontinue if no improvement 1, 2

Second-Line Neuromodulator Therapy

Tricyclic Antidepressants (TCAs)

• Prescribe tricyclic antidepressants (amitriptyline/trimipramine) starting at 10 mg once daily and titrating to 30-50 mg once daily for patients with mixed symptoms, refractory pain, or when insomnia is prominent 2, 3, 8
• These are the most effective first-line pharmacological treatment for mixed IBS (IBS-M) 2
• Educate patients that side effects occur early and benefits may not be apparent for 3-4 weeks 3
• Continue for at least 6 months if the patient reports symptomatic improvement 2
• Caution: TCAs may aggravate constipation 4, 2

Selective Serotonin Reuptake Inhibitors (SSRIs)

• If there is a concurrent mood disorder, use an SSRI instead of low-dose TCAs, because low-dose TCAs are unlikely to address psychological symptoms 2
• Consider SSRIs in low doses for constipation-predominant IBS 3
• Inform patients that anxiety and disturbed sleep may occur during the first 10 days and benefits may not occur for 3-4 weeks 3

Psychological Therapies (For Refractory Cases)

When to Refer to Gastropsychologist

• Refer if IBS symptoms or their impact are moderate to severe, patient accepts that symptoms are related to gut-brain dysregulation, and has time to devote to learning new coping strategies 4, 2
• Also refer if patient shows moderate to severe symptoms of depression or anxiety, suicidal ideation, low social support, impaired quality of life, avoidance behavior, or motivational deficiencies affecting self-management 4

Specific Psychological Interventions

• Initially offer explanation, reassurance, and simple relaxation therapy possibly using audiotapes 4, 2
• Consider IBS-specific cognitive behavioral therapy or gut-directed hypnotherapy when symptoms persist despite pharmacological treatment for 12 months 1, 2, 6
• These brain-gut behavior therapies are specifically designed for IBS and differ from psychological therapies that target depression and anxiety alone 2
• Biofeedback may be especially helpful for disordered defecation 4, 5, 2
• Exclude patients with overt psychiatric disease from hypnotherapy 4

Psychiatric Referral

• Refer to psychiatry or specialist psychologist if patient shows severe psychiatric illness, psychiatric medication use, concern about use or misuse of anxiety medication or opiates, or has an eating disorder 4

Treatment Monitoring and Adjustment

• Review treatment efficacy after 3 months and discontinue ineffective medications 5, 2
• Recognize that symptoms may relapse and remit over time, requiring periodic adjustment of treatment strategy 2
• Measure progress in both physical and psychological domains when assessing responses to psychological treatment 4

Critical Pitfalls to Avoid

• Do not pursue extensive testing once IBS diagnosis is established in patients under 45 without alarm features 5, 1, 2
• Limited investigations (coeliac serology) are needed in suspected IBS, but exhaustive investigation should be avoided 4, 7
• Do not recommend IgG-based food allergy testing, as true food allergy is rare in IBS 5, 1
• Avoid insoluble fiber (wheat bran) as it worsens symptoms 5, 1
• Do not use excessive fiber supplementation as abdominal cramps and bloating may worsen 3
• Avoid reinforcing abnormal illness behavior through repeated unnecessary consultations and procedures 4

Multidisciplinary Care Coordination

• Refer to gastroenterology dietitian if patient consumes considerable intake of foods that trigger IBS symptoms, shows dietary deficits or nutritional deficiency, shows recent unintended weight loss, or requests dietary modification advice 4, 5, 2
• Build collaborative links with gastroenterology dietitians and gastropsychologists to coordinate high-quality care 1, 2
• Inform the patient's referring doctor, general practitioner, or mental health provider about any changes in wellbeing, particularly if there is risk of self-harm or harm to others 4

Addressing Mental Health Comorbidity

• Screen for psychological disorders even if you are not a mental health provider, as gastroenterologists and dietitians may be the first to observe emotional difficulties 4
• Identify features of psychological disorders: sleep and mood disorders, previous psychiatric disease, history of current or past physical/sexual abuse, poor social support, adverse social factors (separation, bereavement), and somatization 4, 2
• Assess whether diagnosed co-occurring psychological disorders (anxiety or depression) are adequately treated, as under-managed anxiety and depression negatively affect responses to IBS treatment 4
• Master patient-friendly language for discussion of the gut-brain axis, its dysregulation, and how depression or anxiety can lead to onset, perpetuation, and/or maintenance of IBS 4