Diarrhea is characterized by loose or watery stools. Most people experience this widespread illness at some point in their lives, with short-term cases of diarrhea being the second most commonly reported illness in the United States.
While acute cases of diarrhea are not usually anything to worry about, chronic diarrhea may cause other problems if not treated.
This article discusses chronic diarrhea, its causes, and the available treatment options.
There are many causes of chronic diarrhea, with some of the most common including:
Excessive alcohol or caffeine intake
Drinking large amounts of alcohol or caffeine-containing drinks such as coffee or cola can cause loose and watery stools.
When a person stops consuming these substances or consumes them in more moderate amounts, symptoms should resolve.
Sugar and dairy
Certain sugars and artificial sweeteners are known to cause diarrhea. If a person consumes these sweet substances every day, they may cause chronic diarrhea.
Examples of such sugars and artificial sweeteners include:
- Sorbitol: This calorie-free sugar substitute is used in candies, chewing gums, and sugar-free items.
- Mannitol: Similar to sorbitol, this sweetener can have a laxative effect.
- Fructose: This naturally occurring sugar is found in fruit and honey. Large amounts of fruit can cause diarrhea due to their high fructose content. It may also be added to candies and sodas.
- Lactose: A natural sugar found in dairy that can cause chronic diarrhea in people who cannot digest it. Approximately 65 percent of people around the world have problems digesting lactose.
Herbs and herbal remedies
Herbal remedies and herbal teas, such as Senna, can contain natural laxatives.
If someone is taking several herbal products, it may be necessary to stop using them all before reintroducing them one at a time. This may help to work out the source of the chronic diarrhea.
Chronic diarrhea can be an adverse effect of both prescription and over-the-counter medications.
Some common medications that can cause diarrhea include:
- most antibiotics, including cefpodoxime, amoxicillin, and ampicillin
- some antidepressants, such as selective serotonin reuptake inhibitors and serotonin-noradrenaline reuptake inhibitors
- antacids containing magnesium hydroxide
- laxatives and stool softeners
- proton pump inhibitors, including omeprazole and lansoprazole
- chemotherapy drugs to treat cancer
Also, diarrhea may signal toxicity from some medications, such as lithium and digoxin.
In some cases, chronic diarrhea can be caused by an intestinal parasite. This is less common in the U.S. than in less developed countries.
A stool test is usually necessary to diagnose a parasitic infection. A biopsy may also be required.
Inflammatory bowel disease (IBD)
Other symptoms of IBD include:
There is no cure for IBD, but people can manage it with medications and lifestyle changes.
- Irritable bowel syndrome (IBS): A functional disorder that can cause diarrhea or constipation, or both.
- Gallbladder removal: Following this procedure, an increase in bile in the colon can lead to diarrhea.
- Hormonal disorders: Examples of hormonal disorders include overactive thyroid disease and diabetes.
- Surgery: Diarrhea can be a complication of some types of abdominal or intestinal surgery.
- Allergies: In rare cases, food allergies can lead to loose and watery stools.
- Rare tumors: For example, carcinoid tumors produce hormones that cause diarrhea.
Chronic diarrhea is characterized by loose or watery stools that continue for 4 weeks or more.
Other symptoms may be present, including:
- increased frequency of bowel movements
- a sense of urgency to pass stool
- stomach cramps
The most serious complication associated with chronic diarrhea is dehydration, which can be life-threatening if not addressed.
Signs of dehydration include:
- dark urine
- dizziness and shakiness
- excessive thirst
A doctor will diagnose chronic diarrhea based on a physical examination. Follow-up tests can help to determine the underlying cause.
During the examination, the doctor will ask about the symptoms and any personal or family history of digestive problems.
It can be helpful for the person to disclose what they eat and drink, their drug use, and travel history.
The doctor may then order:
If the blood tests and stool sample do not reveal any reason for the chronic diarrhea, imaging tests can check for problems in the digestive system.
If the cause remains unknown despite undergoing these tests, the doctor may diagnose IBS. This is a disorder where the digestive system appears normal, but it does not function properly.
Treatment of chronic diarrhea depends on the underlying cause. Some treatment options include the following:
Managing related conditions
Diarrhea that is caused by a medical condition, such as IBD, may resolve once the condition is treated or managed.
It is important to work with a doctor to develop a treatment plan to address the diarrhea and the underlying illness.
Anti-diarrheal medications are a short-term remedy for diarrhea. While they may relieve symptoms, people should not use them on an ongoing basis.
Other medications which may help include:
- antibiotics, for infections that are causing diarrhea.
- codeine-containing medications, which can reduce watery and loose stools.
- over-the-counter medications to slow down the passage of stool through the digestive tract, including bismuth (Pepto-Bismol) and loperamide (Imodium).
Those who are taking medications that can cause chronic diarrhea should talk to their doctor about alternative drugs that do not have this side effect.
Diarrhea can be extremely dehydrating, especially when it persists over an extended period. As a result, it is important to drink clear fluids, such as water, non-caffeinated teas, and low-sodium broths, throughout the day to stay hydrated.
If a specific food or drink is causing chronic diarrhea, it is essential to remove these foods from the diet to see if symptoms improve.
Once the diarrhea clears up, it may be possible to gradually eat these foods again on an infrequent basis, or in moderate amounts.
Keeping a food diary can help people to spot trigger foods.
Other dietary changes that may help include:
- limiting or avoiding caffeine
- limiting or avoiding alcohol
- portion control
Some natural products may help relieve chronic diarrhea. Probiotics can restore a healthy balance of bacteria in the gut.
Some fiber supplements, such as psyllium, can relieve chronic diarrhea. They may be especially helpful for those with IBS or other digestive conditions that cause loose stools.
People should avoid psyllium products that also contain laxatives.
Not all cases of chronic diarrhea are preventable. However, it is possible to reduce the risk of getting chronic diarrhea by taking the following steps:
- keeping a food diary and looking for patterns in food intake and diarrhea symptoms
- discussing the side effects of medications with a doctor
- requesting a change in medications if necessary
- taking probiotic supplements on a regular basis
- drinking only clean or filtered water
- washing hands before and after food preparation
- cleaning and thoroughly cooking meat before eating
- washing fresh produce before eating
- cleaning kitchen surfaces regularly
- washing hands regularly, especially after going to the toilet or coming into contact with someone who is ill
It is important that a person sees a doctor if the diarrhea lasts longer than a few days, or it is accompanied by other symptoms, such as fever and excessive tiredness.
If people notice symptoms of dehydration, they should consult a doctor immediately.
The underlying cause of the chronic diarrhea will determine the outlook.
Those with food intolerances or people who are experiencing diarrhea caused by excessive intake of certain substances will usually experience relief if they avoid or limit the substance that is causing the problem.
For other people, changing medications under the supervision of their doctor will be enough to resolve the condition.
Chronic diarrhea caused by an infection can be treated with antibiotics. If a digestive disorder or other medical condition is causing loose and watery stools, symptoms should gradually resolve once the condition is under control.
The most important step that someone with chronic diarrhea can take is to consult their doctor.