Causes of chronic diarrhea and how to treat it

There are many potential causes of chronic diarrhea. Some of the most common include:

Excessive alcohol or caffeine intake

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Drinking large amounts of alcohol or beverages that contain caffeine, such as coffee or cola, can cause loose and watery stools.

When a person stops consuming these substances or starts to consume them in more moderate amounts, the symptoms should resolve.

Sugar and dairy

Certain sugars and artificial sweeteners may cause diarrhea. Consuming these sweet substances every day can even lead to chronic diarrhea.

Examples of such sugars and artificial sweeteners include:

• Sorbitol: Manufacturers use this calorie-free sugar substitute in candies, chewing gums, and sugar-free items.
• Mannitol: This sweetener can have a laxative effect similar to that of sorbitol.
• Fructose: This naturally occurring sugar is present in fruit and honey. Eating large amounts of fruit can cause diarrhea due to its high fructose content. Food producers may also add fructose to candies and sodas.
• Lactose: This is a natural sugar in dairy that can cause chronic diarrhea in people whose bodies cannot digest it. Around 65% of people around the world have problems digesting lactose.

Herbs and herbal remedies

Herbal remedies and herbal teas, such as senna, may contain natural laxatives.

If a person is using several herbal products at once, it may be a good idea to stop using them all, then reintroduce them one at a time. This may help the person work out which product is the cause of the chronic diarrhea.

Medication

Chronic diarrhea can be an adverse effect of several prescription and over-the-counter (OTC) 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 that contain 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.

Infection

In some cases, an intestinal parasite can give rise to chronic diarrhea. This is less common in the U.S. than in countries with less developed food and water sanitation.

A stool test is usually necessary to diagnose a parasitic infection. A doctor may also carry out a biopsy.

Inflammatory bowel disease

Inflammatory bowel disease (IBD) is an umbrella term for several chronic conditions involving inflammation of the gut. Two of the most common are Crohn’s disease and ulcerative colitis.

Some symptoms of IBD include:

• blood in the stool
• tiredness
• fever
• nausea
• stomach pain and cramps

There is currently no cure for IBD. However, people can usually manage it using medications and by making lifestyle changes.

Other causes

These can include:

• Irritable bowel syndrome (IBS): This is a functional disorder that can cause diarrhea, constipation, or both.
• Gallbladder removal: Following this procedure, more bile may build up in the colon. This may lead to diarrhea.
• Hormonal disorders: Some examples of hormonal disorders include overactive thyroid 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.

The American College of Gastroenterology define chronic diarrhea as a symptom that causes loose or watery stools for 4 weeks or longer.

Other symptoms may be present, including:

• bloating
• more frequent bowel movements
• a sense of urgency to pass stool
• stomach cramps
• nausea

Sometimes, diarrhea can also cause a burning sensation. Learn more about what causes this, plus other symptoms, here.

The most serious complication of chronic diarrhea is dehydration. This can be life threatening if a person does not receive treatment or rehydrate.

Some signs of dehydration include:

• dark urine
• dizziness and shakiness
• excessive thirst
• tiredness
• fever

Learn more about dehydration and how to treat it here.

A doctor will carry out a physical examination to diagnose chronic diarrhea. Follow-up tests can help determine the underlying cause.

During the examination, the doctor will ask about any symptoms the person has experienced, as well as their family medical history. They will primarily focus on any history of digestive problems.

It can also be helpful for the person to disclose what they tend to eat and drink, any medications they are taking, whether or not they drink alcohol or take illicit drugs, and their recent travel history.

The doctor may then request:

• blood tests
• a stool sample to test for inflammation, bacteria, or parasites
• an ultrasound or CT scan

If blood tests and stool samples do not reveal any reason for the chronic diarrhea, the doctor may order imaging tests to check for problems in the digestive system.

If the cause remains unknown despite these tests, the doctor may diagnose IBS. People with this condition have digestive systems that appear normal but do not function as they should.

Treating chronic diarrhea depends on its underlying cause. Some potential treatment options include:

Managing any related conditions

Diarrhea that occurs due to a medical condition, such as IBD, might resolve with treatment of the underlying condition.

It is important to work with a doctor to develop a treatment plan that addresses the diarrhea as well as any underlying illness.

Taking or switching medications

Antidiarrheal medications are a short-term remedy. Although they tend to relieve symptoms, people should not use them on an ongoing basis.

Other medications that may help include:

• antibiotics, for bacterial infections that cause diarrhea
• codeine-containing medications, which can reduce watery and loose stools
• OTC medications to slow down the passage of stool through the digestive tract, including bismuth (Pepto-Bismol) and loperamide (Imodium)

People taking medications that can cause chronic diarrhea should talk to their doctor about alternative drugs that do not have this side effect.

Hydrating

Diarrhea can cause extreme dehydration, especially when it continues over an extended period of time.

As a result, it is important to drink plenty of clear fluids throughout the day. Options include water, noncaffeinated teas, and low sodium broths. This can help people with chronic diarrhea stay hydrated.

Making dietary changes

If a specific dietary item is the cause of the chronic diarrhea, a person can try removing this food or beverage from the diet to see whether or not symptoms improve.

Once the diarrhea symptoms clear up, it may be possible to gradually start eating these foods again on an infrequent basis, or in moderate amounts.

Keeping a food diary can also help people spot trigger foods.

Other dietary changes that may help include:

• achieving better portion control
• limiting or avoiding caffeine
• limiting or avoiding alcohol

Trying natural remedies

Some natural products may help relieve chronic diarrhea. Probiotics, for example, can restore a healthy balance of bacteria in the gut.

Some fiber supplements, such as psyllium, can also relieve chronic diarrhea. They may be especially helpful for those with IBS or other digestive conditions that cause loose stools.

However, people should avoid using psyllium products that also contain laxatives.

Not all cases of chronic diarrhea are preventable. However, it is possible to reduce the risk of chronic diarrhea by:

• keeping a food diary and seeing how cutting particular foods from the diet affect the diarrhea
• discussing the side effects of any current medications with a doctor
• requesting a change in medications if necessary
• taking probiotic supplements regularly
• drinking only clean or filtered water
• washing the hands both before and after food preparation
• cleaning and thoroughly cooking meat before eating it
• washing fresh produce before eating it
• cleaning kitchen surfaces regularly
• washing the hands regularly, especially after using the bathroom or coming into contact with a person who is ill

A person should see a doctor if they have diarrhea that lasts longer than a few days or if other symptoms accompany it, such as fever or fatigue.

If a person notices any symptoms of dehydration, they should consult a doctor immediately.

The underlying cause of the chronic diarrhea will determine its treatment options and outlook.

People with food intolerances or those experiencing substance-related diarrhea will usually find relief if they avoid or limit their intake of the substance in question.

For other people, changing medications under the supervision of their doctor will be enough to resolve the symptom.

Antibiotics are usually successful in treating bacterial infections that cause chronic diarrhea.

If a digestive condition or other medical concern causes loose or watery stools, symptoms should gradually resolve once the person has received treatment for it.

The most important step for recovery is to consult a doctor.