Irritable bowel syndrome (IBS) is a common disorder that affects the large intestine (colon). It commonly causes cramping, abdominal pain, bloating, gas, diarrhoea and constipation. It is a chronic condition that you will need to manage long term. IBS is thought to affect up to one in five people at some point in their life, and it usually first develops when a person is between 20 and 30 years of age. Around twice as many women are affected as men. The condition is often life-long, although it may improve over several years.
Only a small number of people with irritable bowel syndrome have severe signs and symptoms. Some people can control their symptoms by managing diet, lifestyle and stress. Others will need medication and counselling.

Symptoms
The signs and symptoms of irritable bowel syndrome can vary widely from person to person and often resemble those of other diseases. The symptoms of IBS are usually worse after eating and tend to come and go in episodes. Most people have flare-ups of symptoms that last a few days. After this time, the symptoms usually improve, but may not disappear completely.

Among the most common are:
Abdominal pain or cramping which may be relieved by defecation.
A bloated feeling.
Gas
Diarrhoea or constipation - sometimes alternating bouts of constipation and diarrhoea
Mucus in the stool occasionally experiencing an urgent need to go to the toilet.
A feeling that you have not fully emptied your bowels after going to the toilet.
Additional problems
In addition to the main symptoms, some people with IBS experience a number of other problems. These can include:
a lack of energy (lethargy)
feeling sick
backache
bladder problems (such as needing to wake up to urinate at night, experiencing an urgent need to urinate and difficulty fully emptying the bladder)
pain during sex (dyspareunia)
incontinence
many people with the condition may have feelings of depression and anxiety.

Causes
It's not known exactly what causes irritable bowel syndrome, but a variety of factors play a role. The walls of the intestines are lined with layers of muscle that contract and relax in a coordinated rhythm as they move food from your stomach through your intestinal tract to your rectum. If you have irritable bowel syndrome, the contractions may be stronger and last longer than normal, causing gas, bloating and diarrhoea.
Abnormalities in your gastrointestinal nervous system also may play a role. Poorly coordinated signals between the brain and the intestines can make your body over react to the changes that normally occur in the digestive process. This over reaction can cause pain, diarrhoea or constipation.

IBS triggers
Certain foods and drinks can trigger the symptoms of IBS. Triggers vary from person to person, but common ones include:
alcohol
fizzy drinks
chocolate
drinks that contain caffeine - such as tea, coffee or cola
processed snacks - such as crisps and biscuits
fatty or fried food
Keeping a food diary may be a useful way of identifying possible triggers in your diet. Stress is another common trigger of IBS symptoms.

Risk factors
Many people have occasional signs and symptoms of irritable bowel syndrome, but you're more likely to have IBS if you:
Are young. IBS tends to occur in people under age 45.
Are female. Overall, about twice as many women as men have.
Have a family history of IBS.
Have a mental health problem. Anxiety, depression, a personality disorder and a history of childhood sexual abuse are risk factors. For women, domestic abuse may be a risk factor
as well.

When to see a doctor
You should see your doctor if you think you have IBS symptoms, so they can try to identify the cause.

Tests and diagnosis
There are no specific tests for IBS. In most cases, a diagnosis will be based on whether you have typical symptoms of IBS. Your doctor will consider assessing you for IBS if you have had any of the following symptoms for at least six months:
abdominal (stomach) pain or discomfort
bloating
a change in bowel habit - such as passing stools more frequently, diarrhoea and/or constipation
If you fit the IBS criteria, your doctor may suggest a course of treatment without doing additional testing. But if you don't respond to that treatment, you'll likely require more tests.

Treatments and drugs
Because it's not clear what causes irritable bowel syndrome, treatment focuses on the relief of symptoms so that you can live as normally as possible. If your problems are moderate or severe, you may need more than lifestyle changes. Your doctor may suggest and medications.

Dietary changes
Eliminating high-gas foods. If you have bothersome bloating or are passing considerable amounts of gas, your doctor may suggest that you cut out such items as carbonated beverages, vegetables - especially cabbage, broccoli and cauliflower - and raw fruits.
Eliminating gluten. Research shows that some people with IBS report improvement in diarrhoea symptoms if they stop eating gluten (wheat, barley and rye).
Eliminating FODMAPs. Some people are sensitive to types of carbohydrates such as fructose, fructans, lactose and others, called FODMAPs (fermentable oligo-, di-, and monosaccharides and polyols). FODMAPs are found in certain grains, vegetables, fruits and dairy products.
Fibre. People with IBS are often advised to modify the amount of fibre in their diet. There are two main types of fibre: soluble fibre (which the body can digest) e.g. - oats, barley, rye, fruit - such as bananas and apples, root vegetables (such as carrots and potatoes golden linseeds) and insoluble fibre (which the body cannot digest) e.g. - wholegrain, bread, bran, cereals, nuts and seeds.

Medications
A number of different medications can be used to help treat IBS, including:
Antispasmodics.
Laxatives.
Anti motility medicines.
Low-dose antidepressants.
Antibiotics. Some people whose symptoms are due to an overgrowth of bacteria in their intestines may benefit from antibiotic treatment.

General eating tips
Your IBS symptoms may also improve by:
having regular meals and taking your time when eating
not missing meals or leaving long gaps between eating
drinking at least eight cups of fluid a day - particularly water and other non-caffeinated drinks, such as herbal tea
restricting your tea and coffee intake to a maximum of three cups a day
reducing the amount of alcohol and fizzy drinks you drink
limiting fresh fruit to three portions a day
if you have diarrhoea, avoiding sorbitol, an artificial sweetener found in sugar-free sweets, including chewing gum and drinks, and in some diabetic and slimming products

Exercise
Many people find that exercise helps to relieve the symptoms of IBS. Your doctor can advise you on the type of exercise that is suitable for you.

Reducing stress
Reducing your stress levels may also reduce the frequency and severity of your IBS symptoms. Some ways to help relieve stress include:
Relaxation techniques - such as meditation or breathing exercises.
Physical activities - such as yoga.
Regular exercise - such as walking, running or swimming.

Probiotics
Probiotics are dietary supplements that contain so-called "friendly bacteria" that can supposedly restore the natural balance of your gut bacteria when it has been disrupted. Some people find taking probiotics regularly helps to relieve the symptoms of IBS.

Psychological treatments
If your IBS symptoms are still causing problems after 12 months of treatment, your physician may refer you for a type of therapy known as a psychological intervention.
IBS is unpredictable. You may go for many months without any symptoms, and then have a sudden flare-up. With appropriate medical and psychological treatment; you should be able to live a normal, full and active life with IBS.

Author: Resident Physician, MARKS Medical
College & Hospital, Dhaka.