About IBS

Irritable bowel syndrome (IBS) is a common, long-term condition of the digestive system. Symptoms can include stomach cramps, bloating, diarrhoea and/or constipation.

The condition is often lifelong, although the symptoms may change over time. With the right strategies, IBS can be successfully managed.

IBS does not pose a serious threat to your physical health and does not increase your chances of developing cancer or other bowel-related conditions.

The exact cause of IBS is unknown. Many causes have been suggested but none have been proven to lead to IBS.

What is IBS?

IBS symptoms

The symptoms of IBS vary between individuals and affect some people more severely than others. Symptoms can become worse, often during times of stress or after eating certain foods.

You may find some of the symptoms of IBS ease after going to the toilet and moving your bowels.

Main symptoms

The most common symptoms of IBS are:

  • abdominal (stomach) pain and cramping, which may be relieved by moving your bowels
  • a change in your bowel habits – such as diarrhoea, constipation or sometimes both
  • bloating and swelling of your stomach
  • excessive wind (flatulence)
  • occasionally experiencing an urgent need to move your bowels

Other less common symptoms may also be experienced, such as:

  • lack of energy (lethargy)
  • feeling sick
  • heartburn

The symptoms of IBS can also have a significant impact on a person's day-to-day life and, as a result, some people may experience symptoms of low mood and stress.

Non-urgent advice: See your GP if:

  • you think you have IBS type symptoms, so they can try to identify the cause
  • you're feeling anxious or experiencing a change in your mood as this can worsen IBS symptoms

Urgent advice: See your GP urgently if:

You have other symptoms, including:

  • a change in your bowel habits that has lasted for more than six weeks, especially if you are over 50 years of age
  • unexplained weight loss
  • a swelling or lump in your stomach or back passage
  • bleeding from your back passage

These can sometimes be a sign of a potentially more serious condition.

You should also tell your GP if you have these symptoms and a family history of bowel cancer or ovarian cancer.

Further information about managing IBS

Diagnosing IBS

There are no specific tests for IBS. Many cases can be diagnosed based on your symptom history and your GP will undertake some routine blood and stool tests to rule out other conditions.

As the symptoms of IBS are similar to other conditions such as coeliac disease and inflammatory bowel disease, it is important to rule these out.

It is important not to make any dietary changes until these tests have been done. This is particularly important for the blood test for coeliac disease as the result can be affected by your diet.

Private allergy testing (for example hair sampling) is not a reliable way to test for allergies or intolerances. If you are concerned, please talk to your GP.

Managing IBS

The symptoms of irritable bowel syndrome (IBS) can often be managed by changing your diet and lifestyle, and understanding the nature of the condition.

You may find it helpful to:

  • follow a healthy, balanced diet
  • stay hydrated
  • exercise regularly
  • manage your stress levels

Medication is sometimes prescribed for people with IBS to treat the individual symptoms they experience. In some cases, psychological treatments may also be helpful.

Adjusting your diet

The first step in trying to reduce your symptoms of IBS is to follow a healthy, balanced diet. Aim to:

  • eat regular meals including breakfast, lunch and an evening meal (if required, small snacks can be included)
  • avoid missing meals or eating late at night
  • take time over your meals, making time to sit down and chew your food well

Use the Eatwell Guide to help you include foods from each food group in your daily routine.


People with IBS are often advised to modify the amount of fibre in their diet depending on their main symptoms. For example, a lower fibre diet can be beneficial for diarrhoea whereas a higher fibre intake can be beneficial for constipation.

More about adjusting your fibre intake


Having enough fluid is important for overall health. It may also ease your symptoms, especially constipation. This is also particularly important when increasing the fibre in your diet or to replace fluids lost when experiencing diarrhoea.

Try to have at least 8 cups or glasses (1.5-2 litres) of fluid per day (you may need more if you have diarrhoea or are increasing your fibre intake). Good choices include water, sugar free drinks and drinks with no caffeine. Aim to reduce fizzy drinks or those that are high in caffeine.


Caffeine is most commonly found in tea, coffee, energy drinks and cola. If you think caffeine may affect your symptoms, try to reduce it further or eliminate it completely.

Tips to reduce your caffeine intake include:

  • Reduce your intake of tea and coffee and aim to switch to decaffeinated or naturally caffeine-free varieties such as herbal teas.
  • Limit cola and iron brew. Decaffeinated varieties are available, but limiting fizzy drinks generally is best.
  • Energy drinks such as Red Bull, Monster and Rock Star are very high in caffeine and should be avoided.


Alcohol can make IBS symptoms worse. Aim to follow recommendations for safe alcohol intake and drink no more than 14 units per week. Spread these out over three or more days and have regular alcohol-free days.

More about alcohol guidelines

Fatty foods

High fat foods should be limited as part of a healthy diet. They have also been shown to aggravate some IBS symptoms, especially diarrhoea. These foods include:

  • fried foods
  • fast food
  • pastries
  • crisps
  • cakes

To improve health and potential IBS symptoms only include these foods in small amounts and infrequently. Many reduced or low-fat varieties are available for a healthier alternative.


Some sweeteners can cause diarrhoea. Look out for sweetener names ending in the letters ‘ol’ as these are most likely to cause symptoms.

These are found in some sugar-free drinks, sweets, chewing gum and mints. It can also be found in ‘diabetic’ and slimming products. Check the labels and limit these products.

Processed foods

Processed or reheated foods contain resistant starch, which can be difficult for your body to digest. Processed foods include:

  • ready meals
  • potato and pasta salads
  • oven chips
  • part-baked breads

These starches can aggravate wind, bloating and diarrhoea symptoms. To limit these, make your own meals using fresh foods wherever possible.

Easing bloating and cramping

IBS can cause bloating or cramps after eating. There are some things you can do which will ease any bloating or cramping you may have. These include:

  • eating small but regular meals
  • eating oats regularly
  • avoiding foods that are hard to digest such as cauliflower and Brussels sprouts
  • exercising regularly

Low FODMAP diet

If your symptoms do not improve after making changes to your diet, a special diet called the low FODMAP diet may be helpful.

A low FODMAP diet should only be followed with the support of a Specialist Dietitian trained in the low FODMAP process.

A low FODMAP diet isn't suitable for everyone and must only be used following a dietetic consultation.


Probiotics are ‘good bacteria’ found in some foods or supplements. It is suggested that these ‘good bacteria’ can restore the natural balance of your gut bacteria when it has been disrupted.

It is unclear exactly how much of a benefit probiotics offer and which types are most effective and research is ongoing to provide further evidence for the use of probiotics in IBS.

If you want to try a probiotic product, you should take it for at least four weeks to see if your symptoms improve. You should follow the manufacturer's recommendations regarding dosage.

More about probiotics


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

Aim to do a minimum of 150 minutes of moderate-intensity aerobic activity, such as cycling or fast walking, every week.

The exercise should be strenuous enough to increase your heart and breathing rates.

More about physical activity guidelines for adults.


Sometimes medications can be used to help treat IBS, including:

  • antispasmodics – which help reduce abdominal (stomach) pain and cramping
  • laxatives – which can help relieve constipation
  • antimotility medicines – which can help relieve diarrhoea

All medication should be taken following the packet or a doctor's advice.

IBS and your mental health

Due to the effects that IBS can have on your ability to perform day to day activities such as working and socialising, some people may experience changes in their mood.

There is evidence suggesting psychological factors play an important role in IBS, this is due to the link that exists between the brain and gut, often called the “gut-brain connection”. In some people, the gut-brain connection can trigger or worsen symptoms such as diarrhoea, constipation and nausea.

Instead of trying to remove stress altogether, you can focus on managing how much stress you encounter on a daily basis and change the way that you respond to stress.

Some ways to manage stress include:

  • identifying your stressors and see if there are some things within your control to manage or change
  • relaxation techniques – such as breathing exercises, or doing activities that you find relaxing
  • taking time out for friends, family and activities you enjoy
  • regular exercise – such as yoga, walking, running or swimming

You can also listen to NHS Public Health Scotland's podcast, Steps for Stress.

Accessing further support

There are several different types of psychological therapy. They all involve teaching you techniques to help you understand and self-manage your condition more effectively.

The availability of psychological interventions on the NHS may vary between NHS health boards.

Speak to your GP if you have ongoing feelings of low mood, stress or anxiety that are affecting your daily life or impacting your ability to manage your IBS. Your GP will advise on the best support option for you.

Support groups

There is a large community of people with IBS and charities such as GUTS UK and The IBS Network, who can provide further information and advice on how to live well with IBS.

Last updated:
01 March 2022