IBS-D is irritable bowel syndrome (IBS) with diarrhea. It may cause a change in bowel habits alongside abdominal discomfort. Scientists do not know what the exact underlying cause of IBS-D is.

Treatments for IBS-D may include dietary and lifestyle changes, medications, and mental health therapies.

This article looks at the causes, symptoms, and diagnosis of IBS-D, along with treatment options.

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IBS-D is a subtype of IBS that has diarrhea as a main symptom. People may have abdominal pain with frequent bowel movements or loose, watery stools.

Experts are unsure of the exact cause of IBS-D, but it is probably due to many different factors.

Abnormally fast contractions of the intestines may affect how they absorb water from digested foods, causing stools to be looser than usual.

If people have a gut infection, it may lead to IBS-D. This type of IBS-D may be short-term or long-term.

Food sensitivities or allergies may cause IBS-D if people develop symptoms after eating certain foods or drinks. Some people may find that gluten or lactose trigger IBS-D.

Routine allergy testing is not an effective way of identifying IBS trigger foods, so people may have to work it out through elimination diets.

Other possible causes of IBS-D include:

  • increased sensitivity in the gut, which may increase pain or discomfort from intestinal contractions or gas
  • a change in the amount or type of normal gut bacteria
  • stress and anxiety, which may worsen symptoms of IBS-D

Symptoms of IBS-D may include:

  • frequent abdominal discomfort or pain
  • abdominal cramps that may improve with bowel movements
  • frequent or changed bowel movements
  • loose, watery stools
  • abdominal bloating
  • mucus in stools

People may also have constipation at times with IBS-D. Most of these symptoms occur during the daytime. It is unusual for IBS-D to cause diarrhea at night. If people have diarrhea that wakes them from sleep, they need to talk with a doctor.

People may find that certain factors, such as food, anxiety, or stress, trigger IBS-D symptoms.

Symptoms that may occur with IBS-D that do not affect the gut may include:

Learn more about symptoms of IBS here.

To diagnose IBS-D, healthcare professionals may take a full medical history, assess any symptoms, and carry out a physical exam. They may use the Rome criteria to diagnose IBS-D.

One of the main criteria for IBS-D is abdominal pain with a change in bowel movements.

Healthcare professionals may also use other tests, such as blood tests or imaging scans, to rule out other conditions that can cause similar symptoms.

People can manage IBS-D in various ways, including:


Certain medications may help to treat IBS-D. These include:

  • antispasmodic medication, which helps to relax the smooth muscle intestine to reduce IBS symptoms
  • over-the-counter peppermint oil, which may have similar effects to antispasmodics
  • fiber supplements
  • loperamide (Imodium), which is an antidiarrheal medication
  • bile acid binders, which are medications that help the body reabsorb excess bile to reduce diarrhea
  • antibiotics, such as rifaximin (Xifaxan), to alter bacteria levels in the gut
  • pain-relief medication, to specifically block pain in the intestine


Probiotics may help with IBS-D linked to a change in gut bacteria. People may buy probiotics in supplement form or look for yogurt that contains live cultures.

Pectin is a type of fiber in fruits and vegetables. Pectin may help slow down stool movements in the intestines. People may buy it in powder form in the baking section of grocery stores.

People can mix one tablespoon of pectin with 1/4 cup of lemon water and drink it 20–30 minutes before eating.

Learn about complementary therapies for IBS here.

Managing mental health

In some cases, stress and anxiety may be important in IBS-D. People can discuss ways to manage stress and anxiety with a healthcare professional.

Therapies such as cognitive behavioral therapy, hypnosis, or relaxation training may help.

If these are not effective, a doctor may suggest taking medication, such as antidepressants.

A change in diet may help some people to control their IBS-D. A low FODMAP diet may help some people. A low FODMAP diet reduces certain carbohydrates that may trigger gastrointestinal symptoms.

The FODMAP diet may be the most effective elimination diet for managing IBS symptoms.

FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides, and polyols.

The International Foundation for Gastrointestinal Disorders (IFFGD) suggests the following tips for managing chronic diarrhea with diet:

  • Keep a food diary to monitor symptoms relating to foods, drinks, supplements, or changes in mood.
  • Eat smaller meals more frequently throughout the day rather than larger meals.
  • Sit down and relax for 20–30 minutes after eating.
  • Drink plenty of fluids throughout the day at room temperature, but avoid drinking with meals.

The IFFGD note that people should consume foods and drinks that contain sodium and potassium, which are important electrolytes the body can lose through diarrhea.

People may find the BRAT diet helps for short-term management of diarrhea, as it helps to slow down the speed of stools passing through the intestines, which reduces the frequency of bowel movements.

BRAT stands for the foods it includes:

  • Bananas
  • Rice
  • Applesauce
  • Toast

However, the BRAT diet is not a long-term solution as it lacks nutrition.

Learn more about the BRAT diet here.

How long does an IBS-D flare-up last?

IBS-D flare-ups may be different for each person. People may have periods of discomfort or pain followed by very few symptoms.

Flare-ups may be difficult to predict in the beginning, but as people become familiar with their symptoms, they may start to notice a pattern of how long a flare-up lasts.

Why has my IBS suddenly got worse?

Certain factors may trigger or worsen IBS-D. These may include:

  • diet
  • stress
  • infections
  • medications

If people have IBS-D that suddenly worsens with no known cause, they should talk with a healthcare professional.

People will need to contact a doctor if they have IBS-D with any unusual symptoms, such as:

If someone is looking to eliminate certain foods, it may be best to talk with a healthcare professional to ensure people are still getting the right balance of nutrients.

There is currently no cure for IBS-D, but treatments may help to reduce symptoms and improve quality of life.

In some cases, people may be able to completely control their IBS-D through diet and lifestyle changes. In other cases, medications and psychosocial therapy may help.

Noting down symptoms in relation to food, drink, or changes in mood and stress levels may help people identify triggers that worsen their symptoms.

IBS-D is a subtype of IBS. IBS-D is IBS with diarrhea and may cause abdominal discomfort with frequent, loose, or watery stools.

Treatments may include dietary and lifestyle changes, medication, and mental health therapies. People can talk with a healthcare professional about the best way to manage IBS-D.