Irritable Bowel Syndrome (IBS)

Irritable Bowel Syndrome (IBS)

Dr. Widjaja Luman
Consultant Gastroenterologist and General Physician
B Sc (St. Andrews), MB ChB (Man), MRCP (UK), M.D. (Edin),
CCST (UK), FRCP (Edin)


Irritable Bowel Syndrome (IBS) is a very common condition. Approximately one in five people are affected. The pain of IBS is caused by the intestines going into a spasm or cramp and can be quite severe. Abdominal pain or discomfort is accompanied by irregular bowel habits (with diarrhoea or constipation). The combination of pain and irregular bowel habit can affect quality of life. However, IBS is not a life threatening condition in that it is not fatal and usually does not worsen over time. You will find that with some simple changes to your lifestyle, symptoms of IBS can be controlled.

What are the symptoms?

IBS commonly causes the following symptoms :

  • Abdominal cramp which is usually located in the lower part of the stomach. It is often described as sharp, gripping or stabbing pain. Sufferers also often complain of generalized abdominal bloating. Abdominal pain or bloating often eases after passing wind or going to the toilet.
  • Sufferers often complain of having irregular bowel habit. They experience either constipation or loose motions. Some sufferers experience alternating constipation and diarrhea. They experience urgency for defaecation at onset of pain and the pain often eases off after passing wind or defaecation. They also often have the feeling of the need for defaecation even they have just been to the toilet. Patients would describe this symptom as incomplete emptying.
  • Stool consistency which are small, hard, pellety stool or ribbon or pencil like stool.


Less common symptoms are:

  • General lethargy.
  • Backache
  • Headache with sweating, flushing and fainting
  • Nausea or vomiting for no apparent reason
  • Feeling agitated or having pain when going to the toilet


What is the cause of IBS?

There is no known cause of IBS. A lack of fibre (roughage) in the diet, stress and irregular eating times can all make things worse. Quite often the symptom worsens after “life event” or an attack of gastroenteritis (food poisoning or an attack of stomach flu / viral gastroenteritis).

Simple steps which can make positive changes to IBS sufferers are lifestyle and diet. IBS sufferers should have adequate leisure time and regular exercise. It is important to make time for relaxation.

Secondly, eating a healthy and well balanced diet is one of the most important ways to keep yourself healthy and well. Pay more attention to what you eat. Drink at least 8 – 10 cups of fluid a day. Limit intake of tea and coffee as caffeine may worsen symptoms. Caffeine containing drink should not be consumed more than two cups per day.

For sufferers with constipation, eating more fibre may help.   Good sources of fibre are wholemeal bread, cereals, potatoes, wholegrain pasta, brown rice and all types of fruit and vegetables.

Not all IBS sufferers derive benefit from fibre intake. Some IBS sufferers have problem with diarrhoea. If you find that eating more fibre worsens your symptom, you should try cutting down on wholegrain and wholemeal foods instead.

When should I consult my doctor?
Many people suffer from occasional abdominal bloating and constipation. These complaints are usually self limiting and resolve with over the counter medication such as antacids or laxative.

You should see your doctor if:

  • You see blood in your stool. Be aware that BLOOD in the motion is not a symptom of IBS and you should see your doctor as soon as possible if this happens.
  • You suffer from abdominal bloating or pain regularly (several times per week) and for prolonged period (more than two weeks). You have not obtained any relief with over the counter medication.
  • You wake up several times per night with loose motion.
  • Your symptom interferes with work, leisure and /or sleep.
  • You are over 50 years old.
  • Have a family history of colon cancer.
  • Rapid and unintentional weight loss.


What will the specialist do when I consult him?

Depending on the severity and seriousness of your symptoms, your doctor may decide on the necessity of colonoscopy. Colonoscopy is a narrow, flexible tube containing a light source and a small camera at its tip. It is passed through the anus into the large bowel (colon). You need to take medication to purge your bowel one day before colonoscopy.   The procedure is done under sedation. This procedure allows the doctor to examine your large bowel thereby to exclude inflammation, polyp and cancer.

In most situation, simple blood and stool test are all the tests required.

What are the treatments?

There is no cure for IBS. Treatments are targeted at relieving symptoms experienced by patients. First line treatment is usually life style and dietary changes. Some of the life style changes that have been showed to be effective are:

  • Increasing fibre intake if you suffer from constipation. However, excessive fibre can also exacerbate abdominal bloating.       Moderate your fibre intake if abdominal bloating and diarrhoa are your primary complaints.
  • Low FODMAP (fermentable oligo-di-monosaccharide and polyols) is helpful for relieving abdominal bloating.       FODMAP is a group of carbohydrates that are notorious for triggering abdominal bloating and flatus.       Sufferers of these symptoms should try to reduce consumption of food containing FODMAP during exacerbation of symptoms. Some of the FODMAP containing foods are vegetables (garlic, onion, beans and cabbage), fruits (apple, mangoe, plum, water melons), lentils, wheat, dairy products with lactose, high fructose corn syrup, and artificial sweeteners. Artificial sweeteners are commonly found in low calorie soft drinks and chewing gum.
  • Cut down caffeine containing drinks such as tea and coffee. This approach may help with symptom of abdominal cramp.
  • Avoid excessive oily and spicy food
  • Taking probiotics may help with abdominal bloating and constipation.
  • Regular exercise helps with stress control.


Drug therapy is generally targeted to help with specific symptoms of diarrhoea, constipation or abdominal pain. Many sufferers can go for many months without any symptoms. So medication is generally recommended to be taken when necessary. A number of different medications are used to treat IBS symptoms. These are:

  • antispasmodics help to reduce abdominal (stomach) pain and cramping.
  • Laxatives can help to relieve constipation.
  • antimotility medicines can help to relieve diarrhoea.


Low-dose antidepressants may be prescribed to some patients who suffer from frequent bowel motions and abdominal bloating. Commonly used drug is amitriptyline at 10 to 25mg.   The medication is commonly taken at night and it takes about 4 to 6 weeks before beneficial effect is seen.   The medication can be continued for 6 to 12 months.


If your IBS symptoms are still problematic despite above approaches, you may benefit from psychological intervention.   There are several different types of psychological therapy. All these approaches aim to teach you techniques to control your condition better. There is good evidence to suggest they may help some people with IBS. These psychological approaches are hypnotherapy and cognitive behavioral therapy.

Cognitive behavioural therapy (CBT) is a type of psychotherapy that involves teaching you to examine how your beliefs and thoughts are linked to behaviour and feelings, and how to alter your behaviour and way of thinking in order to help you cope with your situation. For hypnotherapy, self hypnosis is used to change your unconscious mind’s attitude towards your symptoms. However, these services are not widely available.


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