Irritable bowel syndrome: what you need to know

What is irritable bowel syndrome?

Irritable bowel syndrome (IBS) is a disorder in which the normal rhythmic movement of your gut (bowel) is disturbed — this can lead to pain, bloating and excessive gas. You may have trouble going to the toilet (constipation), or have very loose and urgent bowel motions or stools (diarrhoea). It is very common — up to one in 5 Australians will have IBS symptoms at some time in their life.

How do you get irritable bowel syndrome?

No one knows exactly what causes irritable bowel syndrome, although stress can make the condition worse. It may be that your system can’t handle some foods, you don’t eat enough bulky food (fibre), or medicines you have taken, such as antibiotics or pain relievers, have disturbed your bowel function. You may have had food poisoning in the past, which can damage nerves in your gut and cause IBS symptoms to start or recur.

How is irritable bowel syndrome diagnosed?

Your doctor will usually make a diagnosis of irritable bowel syndrome from your symptoms. If there is uncertainty about whether you have a more serious problem (e.g. if you have bleeding from the bowel, or considerable weight loss, which do not occur in IBS) your doctor may order other tests such as blood tests, a stool sample test, a sigmoidoscopy (to look at the lining of the last part of your bowel through a lighted tube), a colonoscopy (to look at the lining of your large intestine through a flexible lighted tube) or a barium enema (to view the lining of your bowel on X-ray). If you have IBS, the results of all these tests are likely to be normal.

What does irritable bowel syndrome feel like?

If you have irritable bowel syndrome you may experience the following symptoms:

  • cramps and bloating in your lower abdomen;
  • pain that may be worse on your left side and that usually feels better after you go to the toilet or pass wind;
  • mucus in your stools;
  • diarrhoea — having to go to the toilet too often or urgently and having very loose stools;
  • constipation — not going to the toilet enough, having small, hard stools that might be hard to push out; feeling that you have not finished; or
  • you may have constipation some times, diarrhoea others, and then be fine for a while.

What makes irritable bowel syndrome better?

  • Avoiding or learning how to handle stress: counselling; yoga; breathing exercises; meditation; and relaxation tapes and classes may help.
  • Exercise — being more active helps digestion.
  • Eating well, including consuming a lot of vegetables, fibre (cereals, brans and so on) and water. Add fibre to your diet slowly as it may make things worse at first. Write down what you have been eating, doing and feeling when your gut gets upset, to see if there is any pattern, and try to avoid possible IBS triggers in future.

What makes irritable bowel syndrome worse?

  • Some food and drinks. Each person is different, but foods that may be a problem are fatty foods, sugary foods or those containing sweeteners, ones that cause gas (e.g. carbonated drinks), and milk, chocolate, coffee, tea and alcohol.
  • Eating too quickly or too much.
  • Uncontrolled stress.
  • Some women find that their IBS symptoms are worse when they have their period.

How can my doctor help me with irritable bowel syndrome?

If your IBS symptoms are not being controlled by the measures outlined above, your doctor may prescribe medicines to help with cramping, pain, diarrhoea or constipation. Be careful to use your IBS medicines only at the times that your doctor suggests, rather than using them continuously. While medicines can help relieve some of the symptoms of IBS, no cure is currently available. So modifying your lifestyle is the most important thing you can do.

IBS should not cause blood in the stools, fever, or symptoms that wake you up at night. If you have symptoms like these, or vomiting, dizziness or fainting, you should see your doctor.

What happens if irritable bowel syndrome is not treated?

Irritable bowel syndrome can cause considerable discomfort and distress, but is not life-threatening. Many people worry about cancer, but there is no link between IBS and bowel cancer. See your doctor if you are concerned.

Last Reviewed: 7 December 2009


1. Irritable bowel syndrome [revised September 2006]. In: eTG complete [Internet]. Melbourne: Therapeutic Guidelines Limited; 2009 Nov (Accessed 2009 Dec 10.)
2. National Digestive Diseases Information Clearinghouse [website]. Irritable bowel syndrome (updated 2007, Sep). Available at: (accessed 2009, Dec 10)


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