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

In some cases, medication or psychological treatments may also be helpful.

IBS-friendly diet

Changing your diet will play an important part in controlling your symptoms of IBS. However, there is no "one size fits all" diet for people with the condition. The diet that works best for you will depend on your symptoms and how you react to different foods.

It may be helpful to keep a food diary and record whether certain foods make your symptoms better or worse. You can then avoid foods that trigger your symptoms. However, it's important to remember that these foods will not necessarily need to be avoided for life.

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) and insoluble fibre (which the body cannot digest).

Foods that contain soluble fibre include:

• oats
• barley
• rye
• fruit – such as bananas and apples
• root vegetables – such as carrots and potatoes
• golden linseeds

Foods that contain insoluble fibre include:

• wholegrain bread
• bran
• cereals
• nuts and seeds (except golden linseeds)

If you have diarrhoea, you may find it helps to cut down on the insoluble fibre you eat. It may also help to avoid the skin, pith and pips from fruit and vegetables.

If you have constipation, increasing the amount of soluble fibre in your diet and the amount of water you drink can help.

Your GP may be able to advise on what your recommended fibre intake should be.

Low FODMAP diet

If you experience persistent or frequent bloating, a special diet called the low FODMAP diet can be effective.

FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols. These are types of carbohydrates that aren’t easily broken down and absorbed by the gut. This means they start to ferment in the gut relatively quickly, and the gases released during this process can lead to bloating.

A low FODMAP diet essentially involves restricting your intake of various foods that are high in FODMAPs, such as some fruits and vegetables, animal milk, wheat products and beans.

If you want to try the low FODMAP diet, it’s best to do so under the guidance of a professional dietitian, who can ensure your diet is still healthy and balanced. You can ask your GP or specialist to refer you.

You can read more about the low FODMAP diet on the Kings College London website.

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
• reducing your intake of resistant starch (starch that resists digestion in the small intestine and reaches the large intestine intact), which is often found in processed or re-cooked foods
• limiting fresh fruit to three portions a day – a suitable portion would be half a grapefruit or an apple
• 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
• if you have wind (flatulence) and bloating, it may help to eat oats (such as oat-based breakfast cereal or porridge) and linseeds (up to one tablespoon a day)

Exercise

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.

Read more about health and fitness and physical activity guidelines for adults.

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, pilates or tai chi
• regular exercise – such as walking, running or swimming

If you are particularly stressed, you may benefit from a talking therapy, such as stress counselling or cognitive behavioural therapy (CBT).

Read more about how to manage stress.

Probiotics

Probiotics are dietary supplements that product manufacturers claim can help improve digestive health. They 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. However, there is a little evidence to support this, and it is unclear exactly how much of a benefit probiotics offer and which types are most effective.

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

Medication

A number of different 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
• low-dose antidepressants – which were originally designed to treat depression, but can also help reduce stomach pain and cramping independent of any antidepressant effect

These medications are discussed in more detail below. 

Antispasmodics

Antispasmodics work by helping to relax the muscles in your digestive system. Examples of antispasmodic medicines include mebeverine and therapeutic peppermint oil.

Side effects associated with antispasmodics are rare. However, people taking peppermint oil may have occasional heartburn and irritation on the skin around their bottom.

Laxatives

Bulk-forming laxatives are usually recommended for people with IBS-related constipation. They make your stools softer, which means they are easier to pass.

It's important to drink plenty of fluids while using a bulk-forming laxative. This will help prevent the laxative from causing an obstruction in your digestive system.

Start on a low dose and then, if necessary, increase it every few days until one or two soft stools are produced every one or two days. Do not take a bulk-forming laxative just before you go to bed.

Side effects associated with taking laxatives can include bloating and wind. However, if you increase your dose gradually, you should have few, if any, side effects.

Antimotility medicines

The antimotility medicine loperamide is usually recommended for IBS-related diarrhoea.

Loperamide works by slowing contractions of muscles in the bowel, which slows down the speed at which food passes through your digestive system. This allows more time for your stools to harden and solidify.

Side effects of loperamide can include stomach cramps and bloating, dizziness, drowsiness and rashes.

Antidepressants

Two types of antidepressants are used to treat IBS – tricyclic antidepressants (TCAs) and selective serotonin reuptake inhibitors (SSRIs).

TCAs, such as amitriptyline, are usually recommended when antispasmodic medicines have not been able to control the symptoms of pain and cramping. They work by preventing signals being sent to and from the nerves in your digestive system.

However, TCAs will only start to provide relief after three to four weeks, as your body gets used to the medication.

Side effects of TCAs can include a dry mouth, constipation, blurred vision and drowsiness. These side effects should improve within a few days of starting the medication. Tell your GP if the side effects become a problem – they may prescribe another type of antidepressant.

SSRIs are an alternative type of antidepressant. Examples of SSRIs that are used to treat IBS include citalopram, fluoxetine and paroxetine.

Common side effects of SSRIs include blurred vision, dizziness and diarrhoea or constipation.

Psychological treatments

If your IBS symptoms are still causing problems after 12 months of treatment, your GP may refer you for a type of therapy known as a psychological intervention.

There are several different types of psychological therapy. They all involve teaching you techniques to help you control your condition better, and there is good evidence to suggest they may help some people with IBS.

Psychological treatments that may be offered to people with IBS include:

• psychotherapy – a type of therapy that involves talking to a trained therapist to help you to look deeper into your problems and worries
• cognitive behavioural therapy (CBT) – a type of psychotherapy that involves examining how beliefs and thoughts are linked to behaviour and feelings, and teaches ways to alter your behaviour and way of thinking to help you cope with your situation
• hypnotherapy – where hypnosis is used to change your unconscious mind's attitude towards your symptoms

The availability of psychological interventions on the NHS may vary from region to region.

Complementary therapies

Some people claim therapies such as acupuncture and reflexology can help people with IBS. However, there is no medical evidence to suggest their effectiveness, and they are not recommended.