Irritable Bowel Syndrome
Irritable Bowel Syndrome explained
The Irritable Bowel Syndrome (IBS) consists of a number of symptoms. The term 'syndrome' seems quite grand but it is just the word that doctors use to describe a collection of symptoms. The most important symptoms in IBS are abdominal pain and abnormal bowel habit. Many patients with IBS get crampy abdominal discomfort or pain, which comes and goes, and is often relieved by opening the bowels. The bowel habit is often irregular – sometimes diarrhoea, sometimes constipation and quite often swinging between these two extremes. Some patients may notice they need to get to a toilet in a hurry. Other symptoms vary from individual to individual but include a sensation of bloating, visible abdominal swelling, a sense of incomplete emptying of the bowels and passage of mucus (slime) from the back passage. Many patients notice that they lack energy and sleep poorly.
Irritable Bowel Syndrome is just about the most common disorder of the digestive system and up to one-third of the population experience symptoms from time to time. Women are slightly more affected than men and the usual age for patients to seek advice is between 20 and 40 years. IBS is one of the commonest reasons for patients to visit a GP. In turn it is also a very frequent reason for GPs to refer patients to a hospital specialist.
We do not think that IBS has a single cause. There seem to be many reasons why patients develop the condition. In some people, eating irregularly or taking an abnormal diet may be responsible. Others notice IBS developing after they have had a bout of food poisoning or gastroenteritis. Some people believe that stress makes their symptoms worse. It seems probable, however, that there are other causes which are not yet known.
During digestion the intestine squeezes its contents along our insides towards the anus. This process is usually painless and we do not realise that it is happening unless there is abnormal squeeze within the bowel or, for some reason, the intestine becomes overactive. These changes can be quite painful. Some patients with IBS seem to be very sensitive to the way that their intestines are moving.
Some IBS patients suffer mostly from constipation, some experience diarrhoea, while others have both symptoms at different times. The form of IBS that seems to follow gastroenteritis often leads to persistent diarrhoea. Identifying these different types of IBS is important because treatments often work quite differently depending upon whether diarrhoea or constipation is the main problem. However we do know that the pattern of bowel movements can alter over time and this means that your treatment might need to change should your symptoms vary.
Although the symptoms of IBS can be similar to those seen in more serious conditions, once IBS has been diagnosed there is no reason to think that it will develop into anything more sinister. In particular, patients with IBS are no more likely than anyone else to develop bowel cancer.
You may have had symptoms for many years without seeking help from your doctor, and this is fine as long as you are coping well. Obviously, your doctor is there to help you if symptoms become troublesome or interfere with your life. If you develop any of the alarm symptoms listed on the next page you should certainly ask for advice.
These symptoms are not usually associated with IBS but may be associated with other diseases. If you experience any of these you should see your doctor:
- A change in bowel habit - especially if you are over the age of 40
- Passing blood from the back passage
- Unintentional weight loss of more than 2 kg (4 pounds)
- Diarrhoea waking you from sleep
Your general practitioner will want to rule out other diseases, but will probably be able to make a diagnosis based on the symptoms that you describe. On occasions it may be necessary to do simple blood tests to rule out anaemia, to make sure the liver and thyroid gland are working properly and to exclude any evidence of inflammation within the bowel. You might also have a blood test to look for intolerance to wheat.
A healthy lifestyle may improve symptoms. Particular care should be given to your eating habits and to develop a regular routine for opening your bowels. You may find that particular foods trigger an attack of pain. Keeping a food diary together with a record of bowel symptoms may be helpful since you might be able to see whether there is a pattern. Foods which commonly cause upset include wheat products, dairy products, onions, nuts and caffeine-containing drinks such as coffee, tea and cola. Some patients cannot digest lactose (which is the sugar in milk) and so develop wind and diarrhoea after taking large amounts of milk or dairy products which can include cream, cheese, yoghurt and chocolate.
If a dietary cause is suspected your doctor may be able to give you some advice on what to eat or may suggest that you see a dietitian to identify foods that upset you. You may be asked to leave out particular sorts of foods from your diet, such as wheat, to see whether that helps. Alternatively it might be suggested that you try an ‘exclusion diet’, where a number of different foods which commonly upset patients with IBS are excluded from the diet. If your symptoms improve, individual items can then be added back into your diet until the specific food or foods that seem to upset you are identified. If constipation is the main problem then bulking agents such as natural bran, bran-containing cereals and ispaghula husk (a natural laxative) are helpful.
Drugs to reduce bowel spasm have been used for many years. They are generally very safe and often worth trying. They are mostly available without a prescription and your pharmacist will be happy to advise you. Unfortunately they only benefit a relatively small number of patients. If constipation is your main problem, laxatives either prescribed by your GP or from the pharmacist, will be useful. Some patients benefit from treatment with peppermint oil.
As we begin to learn more about how our intestines work, new drugs are being developed, some of which may help patients whose main symptom is diarrhoea and others who tend to be constipated. Some of these newer agents are not yet available to doctors to prescribe but it does seem likely that a wider range of treatments will be available to patients with IBS in the near future. Sometimes when pain is a major problem, small doses of drugs which are used as antidepressants – such as amitriptyline – can be helpful. These can be useful in patients who have no signs of being depressed.
Hypnotherapy and relaxation therapy have been tried and both have been shown to be effective. Hypnotherapy can be obtained through approved therapists who should be members of the British Medical Hypnotherapy Association. Your doctor may advise on counselling, and some specialists believe that a psychological treatment called cognitive behavioural therapy (CBT) can be useful.
There are indeed many alternative therapies, although none of them has been very carefully assessed in the manner that doctors use to ensure that their treatments are indeed effective. Some patients certainly find that herbal remedies can be helpful but at present there isn’t enough evidence to be sure about this. Aromatherapy and other forms of relaxation can help to relax you, but again we do not know whether they improve bowel symptoms. Many doctors are wary of recommending what they see as unorthodox or unproven treatments although few will object if you wish to try alternative medicines.
The most important question for researchers in IBS is to find out what causes the condition. Knowing this will enable more rational and more effective treatments to be developed. As more and more is revealed about the causes of IBS, it is likely that different patterns of symptoms that patients describe will require differing approaches to treatment. In addition, we need to know more about the mechanism by which specific foods cause IBS as well as how psychological factors can unsettle our insides.