Treatment of Irritable Bowel Syndrome with Diarrhea

First-Line Treatment Options

Regular exercise is recommended to all patients with IBS-D as it can improve symptoms, particularly diarrhea, according to the American Gastroenterological Association 2
First-line dietary advice should include adequate hydration, reducing caffeine and alcohol intake, and increasing soluble fiber, as suggested by the British Society of Gastroenterology 2
Soluble fiber should be started at a low dose and gradually increased to avoid bloating, as recommended by the European Society of Gastroenterology 1, 2
Probiotics may be effective for some patients and can be trialed for up to 12 weeks, discontinuing if no improvement occurs, according to the World Gastroenterology Organisation 2

Tricyclic antidepressants are strongly recommended as effective second-line therapy for global symptoms and abdominal pain, as stated by the American College of Gastroenterology 2, 5
Selective serotonin reuptake inhibitors may be effective for global symptoms, particularly if there is comorbid anxiety or depression, according to the National Institute for Health and Care Excellence 2, 6
5-HT3 receptor antagonists are likely the most efficacious drug class for IBS-D, as reported by the American Gastroenterological Association 2, 5
Eluxadoline is a mixed opioid receptor drug that slows intestinal transit and reduces visceral hypersensitivity, but is contraindicated in patients with prior sphincter of Oddi problems, as warned by the Food and Drug Administration 2, 5

For mild symptoms, start with dietary modifications and lifestyle changes, and add loperamide for diarrhea and/or antispasmodics for pain, as recommended by the British Society of Gastroenterology 2, 6
For moderate symptoms, continue dietary and lifestyle modifications, and add tricyclic antidepressants starting at low dose, as suggested by the European Society of Gastroenterology 2, 5
For severe symptoms, consider 5-HT3 receptor antagonists, rifaximin, or eluxadoline, and integrate psychological therapies such as cognitive behavioral therapy or gut-directed hypnotherapy, as recommended by the American College of Gastroenterology 2, 4, 5, 7

Psychological therapies should be considered at any stage, but are strongly recommended when symptoms are refractory to drug treatment for 12 months, as stated by the National Institute for Health and Care Excellence 3
For patients with comorbid mental health conditions, a multidisciplinary approach involving gastroenterology and mental health specialists is beneficial, according to the World Gastroenterology Organisation 7
Bile acid sequestrants may be considered for patients with cholecystectomy or suspected bile acid malabsorption, as reported by the American Gastroenterological Association 8