Health Dictionary
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Chronic diarrhea medical therapy
Introduction
Overview
Overview
Antidiarrheal drugs can be broadly defined as agents that minimize the symptoms of diarrhea by improving stool consistency, reducing stool frequency, or reducing stool weight. Chronic diarrhea is a common symptom of many conditions. In order to appropriately treat chronic diarrhea, the underlying causes must be identified and treated and, in most cases, the chronic diarrhea will resolve.[1]
Medical Therapy
Medical Therapy
For the treatment of the most common causes of chronic diarrhea, please click below:
- Inflammatory diarrhea
- Watery diarrhea
Summary of Treatment Options for Different Etiologies of Chronic Diarrhea
| Drug/treatment | Mechanism | Typical target daily dosing range | Efficacy of treatment | Adverse effects (with frequency.a) |
| Celiac disease | ||||
| Gluten-free diet | Foods must contain <20 ppm of gluten to be considered gluten-free.[3] | NA | Symptomatic relief typically manifests within days to weeks; however, 22% of patients remain symptomatic after 6 months of therapy.[4] | Constipation
Weight gain |
| Bile acid diarrhea | ||||
| Bile acid sequestrants (off-label use) | Intraluminal bile acid binders | Starting doses:
Cholestyramine: 1 g twice daily Colesevelam: 1250 mg twice daily Colestipol: 1 g twice daily Dose titration based on clinical response.[5] |
A systematic review encompassing 7 RCTs (n = 311) demonstrated that 65.2% of patients with bile acid malabsorption experienced diarrhea resolution compared to 18.6% in the placebo group.[6] | Constipation (11%)
Dyspepsia (8.3%) Nausea (4.2%) Pharyngitis/rhinitis (3.2%) Myalgia (2.1%) |
| Microscopic colitis | ||||
| Budesonide (not FDA approved for this condition) | Anti-inflammatory treatment | 9 mg Daily for 6-8 wk | For collagenous colitis, clinical response was observed in 81% of patients (38/47) vs. 17% (8/47) for placebo (RR, 4.56 [95% CI, 2.43-8.55]).[7]
In the broader microscopic colitis population, response rates were 88% (50/57) for budesonide vs. 38% (22/57) for placebo (RR, 2.03 [95% CI, 1.25-3.33]). |
Gastrointestinal (nausea, dyspepsia, bloating, flatulence) (12%)
Arthralgia, myalgia, abdominal pain, leg cramps (6%) Weight gain (6%) Dizziness (4.5%) |
| Exocrine pancreatic insufficiency | ||||
| PERT (FDA approved for this use) | Porcine derived, including lipase, amylase, and a mixture of proteases | Initial dose: 40 000-50 000 USP units of lipase with meals and half-dose with snacks.[8]
Dose titration based on clinical response Nonenteric-coated enzyme preparations should be given with a proton pump inhibitor |
Patients receiving PERT showed superior improvement in the mean coefficient of fat absorption compared to those on placebo (36.7% vs. 12.1%).[9] | Nausea/vomiting (6%)
Dizziness (4%) Cough (4%) |
| SIBO | ||||
| Rifaximin (off-label use) | Poorly absorbed antibiotic with gram-positive and -negative coverage | Standard dose and duration is 550 mg 3 times daily for 14 d but various regimens have been used, ranging from 600-1000 mg/d for 5-28 d | High-quality evidence for SIBO treatment is currently lacking. However, a meta-analysis of 10 studies (n = 205) indicates that 67.7% (95% CI, 44.7%-86.9%) of patients achieved symptomatic improvement or resolution following successful SIBO eradication.[10] | Nausea (3%)
Elevated liver enzymes (2%) 1 Case of Clostridioides difficile infection |
Abbreviations: FDA= US Food and Drug Administration; NA = not applicable; PERT= pancreatic enzyme replacement therapy; RCT= randomized clinical trial; RR= relative risk; SIBO= small intestinal bacterial overgrowth; USP = United States Pharmacopeia.
a If available.
Medical Therapies for Chronic Diarrhea
Medical Therapies for Chronic Diarrhea
| Medication | Mechanism of action | Recommended dosing | Adverse events (with frequency.a) |
| Over-the-counter agents | |||
| Bismuth subsalicylate | Prostaglandin inhibitor | 524 mg Orally as needed, not to exceed 8 doses in 24-h period | Nausea (12.3%)
Darkening of tongue and stools (89.5%)[11] |
| Loperamide | Peripherally acting as ΞΌ-opioid receptor agonist | 2-16 mg Daily in divided doses | Constipation (5.3%)
Nausea (3.2%) Abdominal cramps (3%) Dizziness (1.4%) Overdose leading to central nervous system depression and arrhythmias (<1%) |
| Prescription agents | |||
| Dicyclomine | Antispasmodics | 10-20 mg Up to every 6 h as needed | Dry mouth/throat (>5%) |
| Hyoscyamine | 0.125-0.25 mg Up to every 6 h as needed | Blurred vision (>5%) | |
| Diphenoxylate-atropine | Peripherally acting ΞΌ-opioid receptor agonists | 1-2 Tablets every 6 h, not to exceed 20 mg of diphenoxylate daily | Fatigue (45.5%).[12]
Dizziness (36.4%) |
| Tincture of opium | 6 mg Every 4-6 h | Nausea (27.3%)
Abdominal pain (27.3%) Overdose and dependence can occur, particularly with tincture of opium | |
| Ondansetron | 5-Hydroxytryptamine 3 receptor agonists | 4-8 mg Every 6-8 h, not to exceed 24 mg daily | Headache (5%)
Constipation (2%) |
| Granisetron | 2-3 mg Daily in single or divided doses | QT prolongation (<2%)
Arrhythmias (<1%) | |
| Amitriptyline | Tricyclic antidepressants.b | 10-100 mg Once daily | Dry mouth (54%) |
| Nortriptyline | 10-100 mg Once daily | Drowsiness (53%)
Difficulty urinating (22%) Blurry vision (17%) | |
| a If available.
b The mechanism of action of tricyclic antidepressants in controlling chronic diarrhea is likely through their anticholinergic effects. | |||
Below are some of the drugs that can be used in the symptomatic treatment of chronic diarrhea and their mechanisms of action. Some drugs have numerous mechanisms of action and can thus be found under more than one section. It is important to know that these drugs are used for the symptomatic treatment of chronic diarrhea. In order to appropriately treat chronic diarrhea, the underlying cause of the disease must be identified.[1]
| Classification | Category | Examples |
| Inhibitors of Intestinal Transit Time | Opiates | Loperamide, Eluxadoline, Diphenoxylate, Difenoxin, Codeine, Opium, Paregoric, Morphine |
| Enkephalinase Inhibitors | Racecadotril | |
| 5-HT3 Receptor Antagonists | Alosetron | |
| Ξ±2-Adrenergic Agonists | Clonidine | |
| Somatostatin and Analogs | Octreotide, Lanreotide, Pasireotide | |
| Calcium Channel Blockers | Nifedipine | |
| Pro-absorptive Agents | Nutrients | Glucose, Amino acids (Oral rehydration solution) |
| Ξ±2-Adrenergic Agonists | Clonidine | |
| Antisecretory Drugs | Somatostatin and Analogs | Octreotide, Lanreotide, Pasireotide |
| Chloride Channel Inhibitors | Crofelemer, Berberine | |
| Calcium Channel Blockers | Nifedipine | |
| Calmodulin Inhibitors | Chlorpromazine, Trifluoperazine | |
| Miscellaneous Antisecretories | Calcium-sensing receptor ligands, Nicotinic acid, Lithium, Zinc, Bismuth, NSAIDs, Corticosteroids, Teduglutide | |
| Intraluminal Agents | Adsorbents | Clays |
| Bile Acid-Binding Resins | Cholestyramine, Colestipol, Colesevelam | |
| Bulk-forming Agents | Fiber |
References
References
- β 1.0 1.1 Schiller LR (1995). “Review article: anti-diarrhoeal pharmacology and therapeutics”. Aliment Pharmacol Ther. 9 (2): 87β106. PMIDΒ 7605866.
- β 2.0 2.1 Singh P, Lee A, Sheth NM, Chey WD (March 2026). “Chronic, Noninfectious Diarrhea: A Review”. JAMA. doi:10.1001/jama.2026.0872. PMIDΒ 41770539 Check
|pmid=value (help). - β Catassi C, Fabiani E, Iacono G, D’Agate C, Francavilla R, Biagi F, Volta U, Accomando S, Picarelli A, De Vitis I, Pianelli G, Gesuita R, Carle F, Mandolesi A, Bearzi I, Fasano A (January 2007). “A prospective, double-blind, placebo-controlled trial to establish a safe gluten threshold for patients with celiac disease”. Am J Clin Nutr. 85 (1): 160β6. doi:10.1093/ajcn/85.1.160. PMIDΒ 17209192.
- β Aggarwal N, Bhatia U, Dwarakanathan V, Singh AD, Singh P, Ahuja V, Makharia GK (January 2025). “Prevalence and etiologies of non-responsive celiac disease: A systematic review and meta-analysis”. J Gastroenterol Hepatol. 40 (1): 101β107. doi:10.1111/jgh.16808. PMIDΒ 39557631 Check
|pmid=value (help). - β Wilcox C, Turner J, Green J (May 2014). “Systematic review: the management of chronic diarrhoea due to bile acid malabsorption”. Aliment Pharmacol Ther. 39 (9): 923β39. doi:10.1111/apt.12684. PMIDΒ 24602022.
- β Soares GA, Godoi A, Marcolin P, Piredda G, Laia E, Rodrigues AZ (April 2025). “Efficacy of Bile Acid Sequestrants in the Treatment of Bile Acid Diarrhea: A Meta-Analysis of Randomized Controlled Trials”. J Clin Pharmacol. 65 (4): 478β485. doi:10.1002/jcph.6154. PMIDΒ 39428959 Check
|pmid=value (help). - β Kafil TS, Nguyen TM, Patton PH, MacDonald JK, Chande N, McDonald JW (November 2017). “Interventions for treating collagenous colitis”. Cochrane Database Syst Rev. 11 (11): CD003575. doi:10.1002/14651858.CD003575.pub6. PMCΒ 6486307. PMIDΒ 29127772.
- β Whitcomb DC, Buchner AM, Forsmark CE (November 2023). “AGA Clinical Practice Update on the Epidemiology, Evaluation, and Management of Exocrine Pancreatic Insufficiency: Expert Review”. Gastroenterology. 165 (5): 1292β1301. doi:10.1053/j.gastro.2023.07.007. PMIDΒ 37737818 Check
|pmid=value (help). - β Safdi M, Bekal PK, Martin S, Saeed ZA, Burton F, Toskes PP (August 2006). “The effects of oral pancreatic enzymes (Creon 10 capsule) on steatorrhea: a multicenter, placebo-controlled, parallel group trial in subjects with chronic pancreatitis”. Pancreas. 33 (2): 156β62. doi:10.1097/01.mpa.0000226884.32957.5e. PMIDΒ 16868481.
- β Gatta L, Scarpignato C (March 2017). “Systematic review with meta-analysis: rifaximin is effective and safe for the treatment of small intestine bacterial overgrowth”. Aliment Pharmacol Ther. 45 (5): 604β616. doi:10.1111/apt.13928. PMCΒ 5299503. PMIDΒ 28078798.
- β Vilaichone RK, Prapitpaiboon H, Gamnarai P, Namtanee J, Wongcha-um A, Chaithongrat S, Mahachai V (2015). “Seven-Day Bismuth-based Quadruple Therapy as an Initial Treatment for Helicobacter pylori Infection in a High Metronidazole Resistant Area”. Asian Pac J Cancer Prev. 16 (14): 6089β92. doi:10.7314/apjcp.2015.16.14.6089. PMIDΒ 26320500.
- β Okdahl T, HΓΈyer KL, Knoph CS, Davidsen L, Larsen IM, Mark EB, Hvas CL, Krogh K, Drewes AM (September 2024). “Opium tincture has anti-propulsive effects in patients with chronic diarrhea: a randomized, placebo-controlled, and cross-over trial”. Scand J Gastroenterol. 59 (9): 1023β1034. doi:10.1080/00365521.2024.2381694. PMIDΒ 39054596 Check
|pmid=value (help).
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Omodamola Aje B.Sc, M.D. [2] Anum Ijaz M.B.B.S., M.D.[3]