Irritable bowel syndrome (IBS) is a common disorder that affects the large intestine (colon). Irritable bowel syndrome commonly causes cramping, abdominal pain, bloating gas, diarrhea and constipation. Despite these uncomfortable signs and symptoms, IBS doesn't cause permanent damage to your colon.
Most people with IBS find that symptoms improve as they learn to control their condition. Only a small number of people with irritable bowel syndrome have severe signs and symptoms.What are the causes of IBS?
Fortunately, unlike more-serious intestinal diseases such as ulcerative colitis and Crohn's disease, irritable bowel syndrome doesn't cause inflammation or changes in bowel tissue or increase your risk of colorectal cancer. In many cases, you can control irritable bowel syndrome by managing your diet, lifestyle and stress
We don't know what causes IBS.
- About half of people with IBS date the start of their symptoms to a major life event – such as change of house or job, or bereavement. This suggests that there may be a psychological trigger for IBS.
- About 10 to 20 per cent of people will date the start of their symptoms to an acute gastroenteritis (inflammation of the stomach that causes vomiting and diarrhoea).
- In the remainder of cases, the trigger factor remains unidentified.
Abnormalities in peristalsis can often be seen in close relatives of people with IBS, although without symptoms. This suggests a trigger sets off the condition in susceptible people.
Nerve-signalling chemicals, particularly serotonin, appear to have an important role.
Many people have occasional signs and symptoms of irritable bowel syndrome, but you're more likely to have IBS if you:
- Are young. IBS begins before the age of 35 for 50 percent of people.
- Are female. Overall, about twice as many women as men have the condition.
- Have a family history of IBS. Studies have shown that people who have a first-degree relative — such as a parent or sibling — with IBS are at increased risk of the condition.
Researchers are studying whether the influence of family history on IBS risk is related to genes, to shared factors in a family's environment, or both
IBS symptoms can start at any age, but they are most common in late teenage years or early adulthood.
The four most common symptoms are:
- abdominal pain
- bloating that usually subsides overnight and returns the following day
You may experience problems in only one part of the gut or in several, and symptoms can change over time.
Your symptoms will depend on which parts of the gut are involved.
Your symptoms will depend on which parts of the gut are involved.
Oesophagus (takes food from mouth to stomach)
- A sensation like a golf ball in the throat between meals, but does not interfere with swallowing.
- 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).
- Severe abdominal bloating and generalised abdominal tenderness associated with bloating.
- Right-sided abdominal pain, either low or tucked up under the right ribs. Does not always get better after passing a stool.
- 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 todiarrhoea.
- Flatulence (excess wind).
- 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 pass a stool.
- Severe, short stabbing pains in the rectum, called proctalgia fugax.
- Feeling of incomplete emptying of bowels.
- Loss of mucus from the rectum (back passage).
- In women, left-sided abdominal pain pain during sex.
- Passing urine more often.
- Fatigue and tiredness.
- Sleep disturbance.
- Loss of appetite.
- Depressive symptoms in about a third of patients.
- Anxiety and stress-related symptoms, which may interact with gut symptoms.
There is no single blood test, X-ray or scan that will diagnose IBS.
The diagnosis is often made on the basis that typical symptoms are present, particularly in younger people who have had at least six months of change in bowel habit, abdominal pain and bloating.
Symptoms, such as pain relieved by opening your bowels and those made worse by eating and passing mucus from the rectum, will help to confirm that you are suffering from IBS.
Blood tests may be taken to exclude other conditions, and occasionally further investigations are performed.
As people with IBS get older, more investigations are performed to ensure the diagnosis is correct – especially if there's:
- unexplained weight loss
- abdominal or rectal masses (unexplained lumps felt by your doctor in the tummy or back passage)
- rectal bleeding
- a family history of bowel or ovarian cancer
- being aged over 60 with a change in bowel habit lasting over 6 weeks.
These may include:
- gastroscopy – examination of the oesophagus, stomach and small intestine with a camera on the end of a long thin tube (endoscope).
- barium studies – a salt that shows up in X-rays of the stomach and intestines.
- colonoscopy – examination of the large intestine with an endoscope
Diet and Lifestyle Changes
Diet and lifestyle changes are important in decreasing the frequency and severity of IBS symptoms.
The first thing your doctor may suggest is to keep a food diary. This will help you figure out foods that trigger your symptoms.
- Limit foods that contain ingredients that can stimulate the intestines and cause diarrhea, such as:
- Dairy products
- Fatty foods
- Foods high in sugar
- Artificial sweeteners (sorbitol and xylitol)
- Some vegetables (cauliflower, broccoli, cabbage, brussels sprouts) and legumes (beans) may worsen bloating and gassiness and should be avoided.
- Dietary fiber may lessen symptoms of constipation.
- Drink plenty of water, and avoid carbonated drinks such as soda, which may cause gas and discomfort.
- Eat smaller meals and eat slowly to help reduce cramping and diarrhea.
- Low fat, high carbohydrate meals such as pasta, rice, and whole-grain breads may help (unless you have celiac disease).
In addition to dietary changes, there are some healthy habits that may also help reduce IBS symptoms.