Chronic diarrhea is defined as loose stools that last for at least four weeks. This usually means three or more loose stools per day. There are many possible causes of chronic diarrhea. Treatment is aimed at correcting the cause of diarrhea (whenever possible), firming up loose stools, and dealing with any complications of diarrhea.
Chronic diarrhea can have a substantial impact on your quality of life and overall health. At its mildest, diarrhea is an inconvenience; at its worst, it may be disabling and even life threatening. Fortunately, effective treatments are available.
This article will focus on causes of chronic diarrhea in developed countries, such as the United States. More detailed information about chronic diarrhea in developed countries is available by subscription. (See "Approach to the adult with chronic diarrhea in developed countries".)
CHRONIC DIARRHEA CAUSES
A wide range of problems can cause chronic diarrhea; some of the most common causes include irritable bowel syndrome (IBS), inflammatory bowel disease (Crohn disease and ulcerative colitis), malabsorption syndromes in which food cannot be digested and absorbed, and chronic infections. There are also many other less common causes of chronic diarrhea.
Irritable bowel syndrome — Irritable bowel syndrome is one of the most common causes of chronic diarrhea. IBS can cause crampy abdominal pain and changes in bowel habits (diarrhea, constipation, or both). IBS can develop after having an infection. (See "Patient information: Irritable bowel syndrome (Beyond the Basics)".)
Inflammatory bowel disease — There are several types of inflammatory bowel disease, two of the most common of which are Crohn disease and ulcerative colitis. These conditions may develop when the body's immune system attacks parts of the digestive tract. (See "Patient information: Crohn disease (Beyond the Basics)" and "Patient information: Ulcerative colitis (Beyond the Basics)".)
Infections — Intestinal infections are a cause of chronic diarrhea. Infections that cause chronic diarrhea can be seen in people who travel or live in tropical or developing countries. Intestinal infections can also develop after eating contaminated food or drinking contaminated water or unpasteurized ("raw") milk. (See "Patient information: Food poisoning (food-borne illness) (Beyond the Basics)".)
Endocrine disorders — An overactive thyroid (hyperthyroidism) can cause chronic diarrhea and weight loss. Diabetes can cause chronic diarrhea if the nerves that supply the digestive tract are injured.
Food allergy or sensitivity — Food allergies and hypersensitivity can cause chronic diarrhea. People with celiac disease are sensitive to gluten, a major component of wheat flour which can cause diarrhea and weight loss. Patients with lactose intolerance develop diarrhea and gas when they ingest milk. (See "Patient information: Celiac disease in adults (Beyond the Basics)".)
Medicines — Medicines (prescription and nonprescription), herbs, and dietary supplements can cause diarrhea as a side effect. To determine if a medicine could be the cause of your diarrhea, review your list of medicines with your doctor, nurse, or pharmacist. This information may also be available on the medicine bottle or paperwork that comes with most prescriptions.
CHRONIC DIARRHEA EVALUATION
You should seek medical attention if you have loose or watery stools that last more than three or four weeks. You may need to be seen sooner than this if you have complications of diarrhea (eg, bloody diarrhea, fever, dehydration, or weight loss) or abdominal pain that interferes with your activities or prevents eating.
During your visit, it is important to mention when your diarrhea began, any recent changes in medicines or medical problems, and if you have had accidents (leaking or smearing of stool in the underwear). Also, provide your doctor with any information about foreign travel and if you are taking medicines for your diarrhea.
Tests — Blood, stool, and urine tests can help to find the underlying cause of diarrhea. Special breath tests are used to test for lactose intolerance, or bacterial overgrowth of the small bowel. If these tests do not find the cause, other approaches may be needed, including x-rays or procedures, such as colonoscopy or sigmoidoscopy. Your primary care provider can order these tests or refer you to a specialist (a gastroenterologist). In many patients with chronic diarrhea, a specific, curable cause cannot be identified. These patients may have irritable bowel syndrome. (See "Patient information: Colonoscopy (Beyond the Basics)" and "Patient information: Flexible sigmoidoscopy (Beyond the Basics)".)
In some cases, your doctor or nurse will recommend a trial of treatment before more invasive tests (see 'Treatment trial' below).
CHRONIC DIARRHEA TREATMENT
Treatment of chronic diarrhea aims to eliminate the underlying cause (if the cause is known), firm up the bowel movements, and treat any diarrhea-related complications.
Treating the cause — The underlying cause of chronic diarrhea should be found and treated whenever possible. For example, infections may be treated with antibiotics. In people with Crohn disease or ulcerative colitis, long-term treatment and follow-up is needed.
In some cases, treatment may be as simple as eliminating a food or medicine.
●For people with lactose intolerance, this may include foods or drinks that contain lactose (table 1).
●Other ingredients that are known to cause diarrhea include sugar-free products made with sorbitol and foods made with fat replacements (eg, Olestra).
●Certain medicines can also cause diarrhea (such as laxatives and antacids).
Treating diarrhea — In some people, the goal is simply to have less diarrhea. This approach is often used before testing, when the results of tests are normal or not helpful, or if diarrhea is caused by a chronic medical problem.
Diarrhea treatments include:
●Bismuth (sold as Kaopectate, Pepto-Bismol)
●Treatments that bulk the stools, such as a high-fiber diet or fiber supplement (see "Patient information: High-fiber diet (Beyond the Basics)")
●Antidiarrhea medicines, such as loperamide (sold as Imodium, available without a prescription) or prescription medicines, such as diphenoxylate (Lomotil)
●Octreotide, a prescription medicine that might be given to people with severe diarrhea
Treatment trial — Your doctor or nurse might recommend trying a treatment before further testing. This approach can help to narrow down the list of possible causes of your diarrhea.
Treatments that might be offered include:
●A trial of antibiotics, for an infection
●Stopping a medicine
●Changing your diet, for a possible food allergy or problem absorbing nutrients (such as lactose intolerance)
Treating complications — Chronic or severe diarrhea can lead to potentially serious complications, including dehydration and malnutrition. While you are being evaluated, you should be sure to drink plenty of fluids. You are drinking enough fluids if your urine is a light yellow color.
If you are not able to drink enough fluids and you become dehydrated, you may be given fluids into a vein (IV) to replace the fluids and electrolytes (salts) lost in diarrhea. This will not cure your diarrhea, but it can prevent more serious complications.
WHERE TO GET MORE INFORMATION
Your healthcare provider is the best source of information for questions and concerns related to your medical problem.
This article will be updated as needed on our web site (www.uptodate.com/patients). Related topics for patients, as well as selected articles written for healthcare professionals, are also available. Some of the most relevant are listed below.
Patient level information — UpToDate offers two types of patient education materials.
The Basics — The Basics patient education pieces answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials.
Patient information: Diarrhea in adults (The Basics)
Patient information: Diarrhea in children (The Basics)
Patient information: Food poisoning (The Basics)
Patient information: High-fiber diet (The Basics)
Patient information: Microscopic colitis (The Basics)
Patient information: Campylobacter infection (The Basics)
Beyond the Basics — Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are best for patients who want in-depth information and are comfortable with some medical jargon.
Patient information: Irritable bowel syndrome (Beyond the Basics)
Patient information: Crohn disease (Beyond the Basics)
Patient information: Ulcerative colitis (Beyond the Basics)
Patient information: Food poisoning (food-borne illness) (Beyond the Basics)
Patient information: Celiac disease in adults (Beyond the Basics)
Patient information: Colonoscopy (Beyond the Basics)
Patient information: Flexible sigmoidoscopy (Beyond the Basics)
Patient information: High-fiber diet (Beyond the Basics)
Professional level information — Professional level articles are designed to keep doctors and other health professionals up-to-date on the latest medical findings. These articles are thorough, long, and complex, and they contain multiple references to the research on which they are based. Professional level articles are best for people who are comfortable with a lot of medical terminology and who want to read the same materials their doctors are reading.
Approach to the adult with chronic diarrhea in developed countries
Clinical features and diagnosis of malabsorption
Clinical manifestations and diagnosis of small intestinal bacterial overgrowth
Clinical manifestations, diagnosis, and prognosis of ulcerative colitis in adults
Epidemiology, clinical manifestations, and diagnosis of cryptosporidiosis
Definition, epidemiology, and risk factors in inflammatory bowel disease
Differential diagnosis of microbial foodborne disease
Epidemiology, clinical manifestations, and diagnosis of giardiasis
Etiology and pathogenesis of small intestinal bacterial overgrowth
Evaluation of the HIV-infected patient with diarrhea
Epidemiology, clinical manifestations, and diagnosis of Cystoisospora infections
Lymphocytic and collagenous colitis (microscopic colitis): Clinical manifestations, diagnosis, and management
Overview of the medical management of mild to moderate Crohn disease in adults
Management of severe ulcerative colitis
Overview of the management of Crohn disease in children and adolescents
Treatment of irritable bowel syndrome in adults
Treatment and prevention of giardiasis
The following organizations also provide reliable health information.
●National Library of Medicine
●National Institute of Diabetes and Digestive and Kidney Diseases