What are the treatment options for Irritable Bowel Syndrome with Diarrhea (IBS D)?

Treatment of IBS-D (Irritable Bowel Syndrome with Diarrhea)

Loperamide at 4-12 mg daily is the most effective first-line pharmacological treatment for IBS-D, significantly reducing stool frequency and urgency. 1

First-Line Treatment Approach

Lifestyle and Dietary Modifications

• Regular exercise should be recommended to all IBS-D patients as it provides significant benefits for symptom management 1
• Identify and reduce excessive intake of lactose, fructose, sorbitol, caffeine, or alcohol in patients with diarrhea, as these commonly trigger symptoms 2, 1
• Trial lactose/fructose/alcohol exclusion if appropriate based on dietary history 2
• Consider a low FODMAP diet under supervision of a trained dietitian for patients with persistent symptoms after initial dietary modifications 1
• Soluble fiber (ispaghula/psyllium) may be beneficial starting with low doses (3-4g/day) and gradually increasing to avoid bloating 1
• Avoid insoluble fiber (wheat bran) as it worsens symptoms in IBS-D 1

Initial Pharmacological Treatment

• Loperamide 4-12 mg daily (either regularly or prophylactically before going out) is the most effective first-line medication for reducing loose stools, urgency, and fecal soiling 2, 1
• Codeine 30-60 mg, 1-3 times daily can be tried but CNS effects are often unacceptable 2
• Cholestyramine may specifically benefit approximately 10% of IBS-D patients who have bile salt malabsorption, particularly those with <5% retention on SeHCAT testing, though it is often less well tolerated than loperamide 2, 1

Second-Line Pharmacological Treatments

For Abdominal Pain

• Antispasmodics with anticholinergic properties (like dicyclomine) show greater efficacy for pain relief compared to direct smooth muscle relaxants 1
• Peppermint oil may be useful as an antispasmodic 2

Neuromodulators

• Tricyclic antidepressants (TCAs) are effective for pain and global symptoms in IBS-D, starting with amitriptyline 10 mg once daily and gradually titrating to 30-50 mg once daily 1
• TCAs are especially useful where insomnia is prominent but may aggravate constipation 2
• Selective serotonin reuptake inhibitors (SSRIs) may be considered if TCAs are not tolerated 1

FDA-Approved Medications for IBS-D

• Rifaximin (XIFAXAN) 550 mg three times daily for 14 days is FDA-approved for IBS-D treatment 3, 4, 5
• Patients who experience symptom recurrence can be retreated up to two times with the same dosage regimen 3
• Eluxadoline (VIBERZI) is FDA-approved for IBS-D in adults 6, 4, 5
• Alosetron (5-HT3 receptor antagonist) is effective as a second-line agent 4, 5

Probiotics

• Probiotics may improve global symptoms and abdominal pain; recommend a 12-week trial and discontinue if no improvement 1

Psychological Therapies

• Consider IBS-specific cognitive behavioral therapy or gut-directed hypnotherapy for patients with symptoms refractory to pharmacological treatment for 12 months 1
• Simple relaxation therapy using audiotapes may be beneficial as an initial approach 2, 1
• Biofeedback is especially helpful for disordered defecation 2
• Psychiatric referral is indicated for serious psychiatric disease 2

Critical Management Principles

Diagnosis and Patient Education

• Those <45 years meeting three or more Rome criteria without sinister symptoms can be given a confident diagnosis without extensive tests 2
• Explain the benign prognosis and relapsing/remitting course 2
• Introduce the concept of brain-gut interaction and how stress may aggravate symptoms or exacerbate worry about the condition 2, 1
• Explain the sensitive/hyperactive gut concept and that some cases are precipitated by bacterial gastroenteritis 2

Treatment Monitoring

• Review treatment efficacy after 3 months and discontinue ineffective medications 1
• If TCAs are effective, continue for at least 6 months 1
• Avoid extensive testing once IBS-D diagnosis is established to prevent reinforcing abnormal illness behavior 2, 1

Common Pitfalls to Avoid

• Do not use anticholinergic antispasmodics in patients with constipation-predominant symptoms as they worsen constipation 2
• Recognize that current treatments have limited value and a specific symptom-targeted approach is required 2
• Formal psychological treatment is expensive but may prove cost-effective if it prevents unnecessary gastroenterological consultations and procedures 2
• Address underlying psychopathological problems to prevent attendance with non-GI functional complaints 2
• Identify features of psychological disorders including sleep and mood disorders, previous psychiatric disease, history of physical/sexual abuse, poor social support, and somatization 2