Irritable bowel syndrome (IBS) is a group of symptoms that occur together, including repeated pain in your abdomen and changes in your bowel movements, which may be diarrhea, constipation, or both.
With IBS, you have these symptoms without any visible signs of damage or disease in your digestive tract.
IBS is a functional gastrointestinal (GI) disorder. Functional GI disorders, which doctors now call disorders of gut-brain interactions, are related to problems with how your brain and your gut work together.
These problems can cause your gut to be more sensitive and change how the muscles in your bowel contract. If your gut is more sensitive, you may feel more abdominal pain and bloating.
Changes in how the muscles in your bowel contract lead to diarrhea, constipation, or both.
What are the symptoms of IBS?
The most common symptoms of irritable bowel syndrome (IBS) are pain in your abdomen, often related to your bowel movements, and changes in your bowel movements.
These changes may be diarrhea, constipation, or both, depending on what type of IBS you have.
Other symptoms of IBS may include
bloating
the feeling that you haven’t finished a bowel movement
whitish mucus in your stool
Women with IBS often have more symptoms during their periods.
IBS can be painful but doesn’t lead to other health problems or damage your digestive tract.
To diagnose IBS, you doctor will look for a certain pattern in your symptoms over time. IBS is a chronic disorder, meaning it lasts a long time, often years. However, the symptoms may come and go.
What causes IBS?
Doctors aren’t sure what causes IBS. Experts think that a combination of problems may lead to IBS. Different factors may cause IBS in different people.
Functional gastrointestinal (GI) disorders such as IBS are problems with brain-gut interaction—how your brain and gut work together.
Experts think that problems with brain-gut interaction may affect how your body works and cause IBS symptoms.
For example, in some people with IBS, food may move too slowly or too quickly through the digestive tract, causing changes in bowel movements.
Some people with IBS may feel pain when a normal amount of gas or stool is in the gut.
Certain problems are more common in people with IBS. Experts think these problems may play a role in causing IBS. These problems include
stressful or difficult early life events, such as physical or sexual abuse
certain mental disorders, such as depression, anxiety, and somatic symptom disorder
bacterial infections in your digestive tract
small intestinal bacterial overgrowth, an increase in the number or a change in the type of bacteria in your small intestine
food intolerances or sensitivities, in which certain foods cause digestive symptoms
Research suggests that genes may make some people more likely to develop IBS.
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