Irritable bowel syndrome (IBS) is a condition characterized by a mixture of symptoms which are believed to be due to a disorder of intestinal motor function or the in-ability of the Qi in the Large Intestine. It is the commonest condition seen by gastroenterologists. The normal gut moves contents along the gut through muscular contractions (propulsion), but also has areas of hold-up (segmentation). The combination of propulsion and segmentation is called peristalsis, and when it is working normally, one is completely unaware of it. The control of peristalsis is complex and the best way to regard irritable bowel is as a loss of co-ordination of these muscular contractions.
Further more, psychological factors are commonly involved (associated with Qi ). This is not to say that the symptoms are not real (they are), but irritable bowel syndrome is often the outcome of a complex interaction between psychological and physical factors.
Some old-fashioned names for irritable bowel syndrome are still in common usage. These include irritable colon, spastic colon and mucous colitis. These are misleading since, the condition not only affects the colon, but also the remainder of the gut.
Although irritable bowel syndrome can be a distressing condition with many unpleasant symptoms, it never causes bowel cancer or other damage to the bowel.
In the UK about 13 per cent of women and 5 per cent of men suffer from IBS.
What Causes IBS Irritable Bowel Syndrome?
Although the cause is unknown, about half of all patients will date the onset of their symptoms to a major life event such as changes of house or job, or bereavement. This suggests that there may be a psychological trigger in susceptible patients. Approximately 10 to 20 per cent of patients will date the onset of their symptoms to an acute gastroenteritis. In the remainder, the trigger factor remains unidentified. The abnormalities in peristalsis mentioned above can often be seen in close relatives of patients (although without symptoms), suggesting that a trigger sets off the condition in susceptible people. Nerve-signalling chemicals, particularly serotonin, appear to have an important role.
What are the symptoms of IBS Irritable Bowel Syndrome?
Symptoms vary from patient to patient, and may occur at any age. However, they most commonly start in late teenage years or early adulthood. The symptoms will depend on which parts of the gut are involved and there is often overlaped between areas of the gut. Some patients may have only one part of the gut involved, while others have several. Moreover, the symptoms may vary over time.
A sensation like a golf ball in the throat between meals which does not interfere with swallowing (globus).
Heartburn - burning pain often felt behind the breastbone.
Painful swallowing (odynophagia), but without hold-up of food.
Sticking of food (dysphagia) - this requires investigation.
Non-ulcer dyspepsia (symptoms suggestive of a stomach or duodenal ulcer, but which has not been confirmed on investigation).
Feeling full after small meals. This may reach the stage of not being able to finish a meal.
Abdominal bloating after meals.
Increased gurgling noises which may be loud enough to cause social embarrassment (borborygmi).
Abdominal bloating which may be so severe that women describe themselves as looking pregnant.
Generalised abdominal tenderness associated with bloating.
Abdominal bloating of both types usually subsides overnight and returns to the following day.
Abdominal bloating of both types usually subsides overnight and returns the following day. Right-sided abdominal pain, either low, or tucked up under the right ribs. Does not always get better on opening the bowels. Pain tucked up under the left ribs (splenic flexure syndrome). When the pain is bad, it may enter the left armpit. Variable and erratic bowel habits alternating from constipation to diarrhoea.
Increased gastro-colic reflex. This is an awakening of the childhood reflex where food in the stomach stimulates colonic activity, resulting in the need to open the bowels. Severe, short stabbing pains in the rectum, called proctalgia fugax.
- Headaches are common.
- In women, left-sided abdominal pain on sexual intercourse is not uncommon.
- Increased frequency of passing urine is common.
- Fatigue and tiredness are very common.
- Sleep disturbance is also frequent.
- Loss of appetite is common, as is nausea.
- Features of depression occur in about one third of patients.
- Anxiety and stress-related symptoms are common and may interact with the gut symptoms.
- Difficulty in swallowing when food gets stuck.
- Indigestion-type pain which wakes the patient at night.
- Abdominal bloating which does not get better overnight.
- Significant and unexplained weight loss.
- The presence of bleeding from the back passage.
- Chronic, painless diarrhoea.