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The symptoms of IBS are usually worse after eating and tend to come and go in bouts.

The symptoms of IBS are usually worse after eating and tend to come and go in bouts.

Most people have a flare-up of symptoms that lasts two to four days. After this time, the symptoms usually improve but do not disappear completely.

The most common symptoms of IBS are:

  • abdominal pain and cramping - often relieved by emptying your bowels
  • a change in your bowel habits - such as diarrhoeaconstipation, or sometimes both
  • bloating and swelling of your abdomen
  • excessive wind (flatulence)
  • an urgent need to go to the toilet
  • a feeling that you need to open your bowels even if you have just been to the toilet
  • a feeling you have not fully emptied your bowels
  • passing mucus from your bottom 

Due to the embarrassment, pain and discomfort of IBS, many people with the condition also have feelings of depression and anxiety.

Bowel symptoms

There are three main patterns of bowel symptoms in IBS. They are:

  • IBS with diarrhoea - when you have repeated bouts of diarrhoea
  • IBS with constipation - when you have repeated bouts of constipation
  • IBS mixed - when you have repeated bouts of diarrhoea and constipation

These patterns are not set in stone. You can switch from one to another and go for long periods with few or no symptoms at all.

Find out about the foods and drinks that can trigger the symptoms of IBS.

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The exact cause of irritable bowel syndrome (IBS) is unknown, but most experts agree that it is related to an increased sensitivity of the entire gut.

The exact cause of irritable bowel syndrome (IBS) is unknown, but most experts agree it is related to an increased sensitivity of the entire gut.

This can be caused by:

  • a change in your body's ability to move food through your digestive system
  • becoming more sensitive to pain from your gut 
  • psychological factors
  • an episode of food poisoning

Digestion process

Your body usually moves food through your digestive system by squeezing and relaxing the muscles of the intestines in a rhythmic way.

However, in IBS it is thought this process is altered, resulting in food moving through your digestive system either too quickly or too slowly. Either way, there will be discomfort within the abdomen.

If food moves through your digestive system too quickly, you will have diarrhoea because your digestive system does not have enough time to absorb water from the food.

If food moves through your digestive system too slowly, you will have constipation because too much water is absorbed, making your stools hard and difficult to pass.

It may be that food does not pass through the digestive systems of people with IBS properly because the signals that travel back and forth from the brain to the gut, controlling the nerves, are disrupted in some way.

An increase in levels of a chemical called 5-hydroxytryptamine (5-HT), which can occur after eating certain foods or during times of stress, is also thought to affect the normal functioning of the gut.

Increased sensitivity

Many sensations in the body come from your digestive system. For example, nerves in your digestive system relay signals to your brain to let you know if you are hungry or full, or if you need to go to the toilet.

Some experts think that people with IBS may be oversensitive to the digestive nerve signals. This means mild indigestion that is barely noticeable in most people becomes distressing abdominal pain in those with IBS.

Psychological factors

There is a fair amount of evidence to suggest psychological factors play an important role in IBS.

However, this does not mean that IBS is "all in the mind", because symptoms are very real. Intense emotional states such as stress and anxiety can trigger chemical changes that interfere with the normal workings of the digestive system.

This does not just happen in people with IBS. Many people who have never had IBS before can have a sudden change in bowel habits when faced with a stressful situation, such as an important exam or job interview.

It has also been discovered that many people with IBS have experienced a traumatic event, usually during their childhood, such as abuse, neglect, a serious childhood illness or bereavement.

It is possible that these types of difficult experiences in your past may make you more sensitive to stress and the symptoms of pain and discomfort.

IBS triggers

Certain foods and drinks can trigger the symptoms of IBS. Triggers vary from person to person, but the most 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 food
  • 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. Therefore, finding ways to manage stressful situations is an important part of treating IBS.

Read more about treating IBS.

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There are no specific tests for IBS, as it does not cause any obvious detectable abnormalities in your digestive system.

There are no specific tests for IBS, as it does not cause any obvious detectable abnormalities in your digestive system.

If you have the symptoms of IBS, your GP will not always need to order blood tests to help diagnose you.

However, in a few cases they may recommend blood tests to rule out other conditions that cause similar symptoms, such as an infection or coeliac disease (a stomach condition caused by gluten intolerance).

IBS is usually diagnosed by carrying out a physical examination and checking whether your symptoms match those typical of the condition.

Your GP will suspect you have IBS if one of the following criteria applies to you.

  • you have abdominal pain or bloating that is relieved when you pass a stool
  • you have abdominal pain or bloating associated with episodes of diarrhoea or constipation
  • you are passing stools more frequently than normal

If you have at least two of the following symptoms, a diagnosis of IBS will be confirmed:

  • a change in how you pass stools, such as needing to strain, feeling a sense of urgency or feeling you have not emptied your bowels properly
  • bloating, hardness or tension in your abdomen
  • your symptoms get worse after eating
  • you pass mucus from your back passage

Further tests

Further tests are usually only needed when you have certain "red flag" symptoms that indicate you may have another serious condition. These symptoms include:

  • unexplained weight loss
  • a swelling or lump in your abdomen or back passage
  • bleeding from your back passage
  • anaemia (a lack of red blood cells)

Further testing may also be recommended if you have a family history of bowel cancer or ovarian cancer, or if you are over 60 years of age and you have had a change in your bowel habits that has lasted for more than six weeks.

Tests you may have include:

  • sigmoidoscopy  where a sigmoidoscope (a thin, flexible tube with a small camera and light at one end) is used to examine your back passage and the lower section of your bowel
  • colonoscopy  where a device similar to a sigmoidoscope, called a colonoscope, is used to examine your entire bowel
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As irritable bowel syndrome (IBS) is not life-threatening, people who do not understand the condition are sometimes quick to trivialise it.

As irritable bowel syndrome (IBS) is not life-threatening, people who do not understand the condition are sometimes quick to trivialise it.

However, the symptoms of IBS often have a significant impact on a person's day-to-day life. The pain, discomfort and inconvenience of IBS is very real and can have a deep psychological effect.

For example, it is estimated that three out of four people with IBS will have at least one episode of depression, and just over half will develop generalised anxiety disorder (GAD). This is a long-term condition that can cause feelings of unease, worry or fear.

You should visit your GP if you are feeling anxious or depressed. These conditions rarely improve without treatment and they could make your IBS symptoms worse.

Your GP will be able to recommend an effective treatment programme for you, such as antidepressants or cognitive behavioural therapy (CBT), or a combination of the two.

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After having irritable bowel syndrome (IBS) for more than 20 years, Ansar Ahmed Ullah is learning to live with the condition.

After having IBS for more than 20 years, Ansar Ahmed Ullah is learning to live with the condition.

"I think my IBS came from too many curries!" says Ansar Ahmed Ullah. He first came to London in the early 1980s. Living in shared accommodation, he relied on spicy takeaways for his main meal in the evening. "We'd also go to the community centre at lunchtime, where they served curry and rice," he remembers.

In the mid-1980s, Ansar started to suffer from frequent constipation, bloating, occasional diarrhoea and stomach pain. On one occasion, the pain was so bad that he was rushed to hospital. "I was there for a week," he remembers. "The doctors gave me all kinds of tests. They thought I might have a stomach ulcer, but they didn't find anything."

Eventually, Ansar spoke to his GP, who diagnosed IBS. He was prescribed painkillers and a muscle relaxant drug to ease his constipation. Unfortunately, neither drug was effective. Ansar decided to try to treat himself.

He joined the IBS Network to learn about his condition. He had several food allergy tests and discovered that he was sensitive to wheat, spicy food and dairy products.

"Luckily, I'm still able to eat chicken and fish," he says. "Avoiding dairy and wheat is very difficult. I love milk in my tea. I've never been able to stand the taste of soya, and I love bread and biscuits. I've found the wheat-free ranges at the supermarkets very helpful, though."

Ansar says he's tried every IBS remedy on the market. "I've more or less resigned myself to the fact that I'm not going to be cured of IBS," he says. "But it can be very difficult.

"The mornings are the worst. When I was employed, I was constantly late because I had to spend so long in the toilet with constipation. There's not a lot of awareness of IBS, particularly among young people, so it's hard for people to understand what you're going through."

Ansar says IBS also affects his relationship with his partner. "She does sometimes get annoyed when she needs to go somewhere in a hurry and I'm still in the toilet. It's also very awkward when you're out and about and you need to use a loo suddenly or for a long period of time. The IBS is in the back of my mind all the time. I have to consider it when I go anywhere or do anything."

However, Ansar tries not to let his IBS get him down. "I do my best to stick to my wheat-free diet and I make sure I eat plenty of fruit. I've found that really helps the constipation. I'm also planning to take more exercise. I already go to Pilates classes and I've got a bike, which I should really use more! I think I'm learning to live with my IBS."

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Geoff Lyon, 57, has had severe IBS since early childhood. He tells us his story.

Geoff Lyon, 57, has had severe IBS since early childhood. He tells us his story.

"It all started when I was about eight years old. I was getting a lot of unexplained diarrhoea and feeling sick. I couldn't go anywhere without wanting to go to the toilet. My parents didn't understand what was wrong with me.

"As I grew up, it didn't get any better. I was still suffering diarrhoea and nausea, as well as constipation, headaches and feeling tired all the time. Sometimes it would wake me up at night and I'd sit for a couple of hours on the toilet sweating, with a severe cramping pain in my gut. I wouldn't be able to go, then suddenly I'd have a gush of diarrhoea. I would be exhausted the next day.

"It wasn't until 1980, when I was 29, that I was referred to hospital to have a barium enema (when the colon is filled with a liquid that shows up on X-ray) and a blood test. They couldn't find anything seriously wrong and eventually diagnosed irritable bowel syndrome (IBS). I was relieved to finally have a diagnosis.

"I was given an antispasmodic drug to take two to three times a day, which slows the contractions in your gut. I now control my IBS with codeine phosphate, an antidiarrhoeal drug.

"Not only has the treatment helped, but also cutting dairy products from my diet. About nine years ago my doctor suggested I try a non-dairy diet. It seems to help. I've always loved milk and cream, so it was difficult switching from them to soya products, but it's worth it. One Christmas I gave in and had some cream trifle. Within half an hour I was on the toilet, which proves it isn't good for me.

"At the moment I still get attacks quite frequently, but they're not as bad and I'm more in control of them. I know when I'm going to have an attack, as I become really lethargic and my stomach distends the night before, like I'm six months pregnant.

"I've noticed that if I'm stressed, my IBS kicks in a couple of days later, so I try to relax and remove any stress from my life.

"I run a self-help group for the IBS Network, which I'd recommend joining. You get lots of factsheets and a 'Can't Wait Card' that you can show to hotels or shops if you desperately need to use their toilet facilities."

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