What is irritable bowel syndrome (IBS)?

Irritable bowel syndrome, or IBS, is a group of symptoms that affect your digestive system. It’s a common but uncomfortable gastrointestinal disorder. People with IBS get excessive gas, abdominal pain and cramps.

What is a functional GI disorder?

IBS is a type of functional gastrointestinal (GI) disorder. These conditions, also called disorders of the gut-brain interaction, have to do with problems in how your gut and brain work together.

These problems cause your digestive tract to be very sensitive. They also change how your bowel muscles contract. The result is abdominal pain, diarrhea and constipation.

What are the different types of IBS?

Researchers categorize IBS based on the type of bowel movement problems you have. The kind of IBS can affect your treatment. Certain medicines only work for certain types of IBS.

Often, people with IBS have normal bowel movements some days and abnormal ones on other days. The type of IBS you have depends on the abnormal bowel movements you experience:

  • IBS with constipation (IBS-C): Most of your poop is hard and lumpy.
  • IBS with diarrhea (IBS-D): Most of your poop is loose and watery.
  • IBS with mixed bowel habits (IBS-M): You have both hard and lumpy bowel movements and loose and watery movements on the same day.

How does IBS affect my body?

In people with IBS, the colon muscle tends to contract more than in people without the condition. These contractions cause cramps and pain. People with IBS also tend to have a lower pain tolerance. Research has also suggested that people with IBS may have excess bacteria in the GI tract, contributing to symptoms.

What are other names for IBS?

You may hear these names for IBS:

  • Irritable bowel.
  • Irritable colon.
  • Spastic colon.
  • Nervous stomach, since symptoms often happen when you’re feeling emotional stress, tension and anxiety.

Who is at risk for developing IBS?

The condition most often occurs in people in their late teens to early 40s. Women can be twice as likely than men to get IBS. IBS may happen to multiple family members.

You may be at higher risk if you have:

What triggers IBS?

If you have IBS, you may have noticed that certain things trigger symptoms. Common triggers include some foods and medication. Emotional stress can also be a trigger. Some researchers suggest that IBS is the gut’s response to life’s stressors.

How common is IBS?

Experts estimate that about 10% to 15% of the adult population in the United States have IBS. However, only 5% to 7% receive an IBS diagnosis. It’s the most common disease that gastroenterologists diagnose.

What are the causes of IBS?

Researchers don’t exactly know what causes IBS. They think a combination of factors can lead to IBS, including:

  • Dysmotility: Problems with how your GI muscles contract and move food through the GI tract.
  • Visceral hypersensitivity: Extra-sensitive nerves in the GI tract.
  • Brain-gut dysfunction: Miscommunication between nerves in the brain and gut.

What are IBS symptoms?

Symptoms of IBS include:

  • Abdominal pain or cramps, usually in the lower half of the abdomen.
  • Bloating.
  • Bowel movements that are harder or looser than usual.
  • Diarrhea, constipation or alternating between the two.
  • Excess gas.
  • Mucus in your poop (may look whitish).

Women with IBS may find that symptoms flare up during their periods. These symptoms often happen again and again, which can make you feel stressed or upset. As you learn management techniques and gain control over flare-ups, you’ll start to feel better, physically and mentally.

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