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Irritable Bowel Syndrome (IBS)


The Manual's Editorial Staff

Reviewed/Revised Apr 2023
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What is irritable bowel syndrome (IBS)?

Your bowels are your intestines, which are part of your digestive system. Your bowels are where food is digested and nutrients are absorbed (taken into) your body. The part of food that isn't taken into your body becomes stool (poop).

  • IBS is a common disorder that is uncomfortable but not dangerous

  • IBS changes your bowel movement (pooping) patterns and makes your lower belly hurt

  • Your bowels may move more (diarrhea) or move less (constipation)

  • Foods you eat and your emotions can sometimes trigger (set off) symptoms

  • Taking medicine and changing the foods you eat may help your symptoms

Digestive System

The Digestive System

What causes IBS?

Doctors don’t know what causes IBS. People with IBS seem to have a sensitive digestive system. Tests on people with IBS don’t show any particular problems.

Certain foods you eat and your eating habits may trigger or worsen your symptoms, such as:

  • Fatty meals, including fried foods

  • Foods that your body can’t easily break down, such as wheat, dairy (like milk or cheese), beans, chocolate, coffee, tea, artificial sweeteners, or certain fruits (like apricots) and vegetables (like asparagus or broccoli)

  • Eating very large meals

  • Eating too quickly or waiting too long to eat

Other factors can also trigger your symptoms, including:

  • Emotions, such as stress, anxiety, depression, and fear

  • Medicines

  • Hormones

You may not always get symptoms after a usual trigger. Symptoms often appear without any known trigger.

What are the symptoms of IBS?

Symptoms come and go. Sometimes you'll feel fine, and sometimes you'll have symptoms. Symptoms often include:

  • Dull aching or cramps in your lower belly that get better after you poop

  • Feeling that your belly is bloated or swollen

  • Constipation or diarrhea

  • A change in the texture of your stool (poop that is lumpy and hard if you have constipation or soft and watery if you have diarrhea)

  • Slimy substance (mucus) in your stool

  • A feeling that you’re not getting all the stool out of your body

How can doctors tell if I have IBS?

There is no test for IBS. Doctors will diagnose IBS based on your symptoms. However, doctors will usually do tests to make sure your symptoms are not caused by other, more dangerous, problems.

How do doctors treat IBS?

Treatment differs from person to person. If certain foods seem to cause your symptoms, doctors may tell you to change your diet.

  • If you have diarrhea or constipation, eat low-fat foods

  • If you have gas, avoid beans and cabbage

  • Limit your use of sorbitol (an artificial sweetener in some foods, medicines, and gum)

  • Limit how much fructose (the sugar in fruits and some plants) you eat

  • If you get constipated, eat more fiber (fiber is in certain foods or in a powder you buy and mix with water)

Doctors may also tell you to:

  • Eat slowly

  • Eat smaller meals more often (such as 5 small meals, not 3 large meals, a day)

  • Take medicines to help with your symptoms

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