Irritable Bowel Syndrome (IBS): The Complete Guide to Symptoms, Diet and Relief

Irritable bowel syndrome (IBS) is one of the most common long-term conditions in the world. Depending on how it is measured, it affects somewhere between one in twenty and one in ten people, and many more live with symptoms they have never discussed with anyone. IBS does not damage the bowel or shorten life, but it can shape almost every part of daily life: what you eat, where you go, how you work, and how you feel about your own body.

This complete guide explains what IBS is and is not, the different types, how it is diagnosed, the warning signs that need further tests, and the treatments with the strongest evidence, from simple diet changes and the low FODMAP diet to medicines and gut-directed psychological therapies. It is written for anyone living with IBS, caring for someone who has it, or working in healthcare.

What is irritable bowel syndrome?

IBS is a disorder of gut-brain interaction. That is the modern term used by gastroenterologists to describe conditions in which the gut looks normal on tests but does not function normally. In IBS, several things combine:

• Visceral hypersensitivity: the nerves of the gut are more sensitive, so normal amounts of gas or stretching are felt as pain or discomfort.
• Altered gut motility: food and waste may move too quickly (causing diarrhoea) or too slowly (causing constipation), or alternate between the two.
• Gut-brain communication: signals between the brain and the gut are amplified. Stress, anxiety and low mood can increase gut symptoms, and gut symptoms in turn increase stress.
• Changes in the gut microbiome: differences in the bacteria living in the gut may play a role in some people.
• Low-grade immune activation: some people develop IBS after a bout of gastroenteritis, known as post-infection IBS.

IBS is real. It is not “all in the head”, and it is not imagined. But because the brain and gut are so closely connected, treatments that work on the brain-gut axis can help the gut, and this is one of the most important things to understand about IBS.

What IBS is not

IBS is not inflammatory bowel disease (IBD). IBD includes Crohn’s disease and ulcerative colitis, which cause visible inflammation and damage to the bowel, bleeding, weight loss, and raised inflammatory markers in blood and stool tests. IBS does not cause bleeding, does not lead to cancer, and does not cause permanent damage to the gut.

IBS is also not coeliac disease, although the symptoms can be very similar. Coeliac disease is an autoimmune reaction to gluten that damages the small intestine, and it is diagnosed with a blood test and, often, a biopsy. Because the symptoms overlap, coeliac disease should be tested for in anyone with IBS-type symptoms, especially before going gluten-free.

Common symptoms of IBS

The core symptom of IBS is recurrent abdominal pain or discomfort linked to bowel movements. Other common symptoms include:

• Bloating and a feeling of fullness, often worse as the day goes on.
• Visible swelling of the abdomen (distension).
• Diarrhoea, constipation, or a mix of both.
• Urgency: a sudden, strong need to open the bowels.
• A feeling of incomplete emptying after a bowel movement.
• Passing mucus (clear or white slime) with stools.
• Excess wind.
• Pain that eases, or sometimes worsens, after opening the bowels.

Many people with IBS also have symptoms outside the gut, including tiredness, back pain, headaches, needing to pass urine often, painful periods, pain during sex, and poor sleep. Anxiety and depression are more common in people with IBS, both as a cause and as a consequence of living with unpredictable symptoms.

The types of IBS

IBS is usually grouped by the main bowel habit on days when bowel movements are abnormal:

• IBS-D (diarrhoea-predominant): loose or watery stools are the main problem, often with urgency.
• IBS-C (constipation-predominant): hard, lumpy stools, straining and infrequent bowel movements dominate.
• IBS-M (mixed): both hard and loose stools occur, sometimes on the same day.
• IBS-U (unclassified): symptoms do not fit neatly into any group.

The type matters because some treatments help diarrhoea and others help constipation. Your type can also change over time. A useful tool is the Bristol Stool Form Scale, which describes stools from type 1 (separate hard lumps) to type 7 (entirely liquid). Types 3 and 4 are considered normal.

What causes IBS?

There is no single cause. IBS develops from a combination of factors that vary from person to person:

• Gastroenteritis: around one in ten people develop IBS after a bacterial or viral gut infection, such as food poisoning or traveller’s diarrhoea.
• Stress and early-life adversity: difficult experiences in childhood and ongoing stress are linked to a higher risk.
• Genetics: IBS can run in families.
• Female sex: IBS is more commonly diagnosed in women, and symptoms often change with the menstrual cycle.
• Antibiotics and changes to the microbiome.
• Diet: certain foods do not cause IBS, but they can trigger symptoms in a sensitive gut.

How IBS is diagnosed

For many years, IBS was treated as a “diagnosis of exclusion”, meaning that many tests were done to rule out everything else first. Modern guidelines recommend a positive diagnosis: in people with typical symptoms and no warning signs, IBS can be confidently diagnosed after a small number of simple tests. This saves people from unnecessary invasive procedures and lets them move on to treatment sooner.

Diagnostic criteria, known as the Rome IV criteria, describe IBS as recurrent abdominal pain on average at least one day a week in the last three months, associated with two or more of: pain related to bowel movements, a change in how often you go, or a change in the form or appearance of stools. Symptoms should have started at least six months before diagnosis.

Typical tests for adults with suspected IBS include:

• A full blood count, to look for anaemia.
• Blood tests for inflammation, such as C-reactive protein.
• A coeliac disease blood test.
• A stool test for faecal calprotectin, which helps distinguish IBS from inflammatory bowel disease in people with diarrhoea.
• Sometimes a stool test for infection, thyroid tests, or tests for bile acid diarrhoea.
• For women over around 50 with persistent bloating, a blood test for CA-125 and further tests may be recommended to rule out ovarian cancer.

Colonoscopy is not needed for most younger people with typical IBS and normal tests. It is recommended when there are red flags, and for bowel cancer screening at the ages set by your country’s screening programme.

Red flags: when symptoms need further investigation

Contact a healthcare provider promptly if you have any of these, because they are not typical of IBS:

• Blood in your stools or black, tarry stools.
• Unintentional weight loss.
• A change in bowel habit that has lasted more than a few weeks, especially after the age of 50.
• Symptoms that wake you from sleep.
• A lump in your abdomen or back passage.
• Anaemia or iron deficiency.
• Persistent fever.
• A family history of bowel cancer, ovarian cancer, coeliac disease or inflammatory bowel disease.
• Persistent bloating in women over 50.

Seek urgent care if you have severe abdominal pain that does not settle, heavy bleeding, persistent vomiting, or signs of dehydration such as dizziness, very little urine and confusion.

First steps: general diet and lifestyle advice

For many people, simple changes reduce symptoms significantly. These are usually tried first, before more specialised diets:

• Eat regular meals at roughly the same times each day. Avoid skipping meals and then eating large portions.
• Eat slowly and chew well. Rushed meals increase swallowed air and bloating.
• Drink enough fluid, mainly water, through the day.
• Limit caffeine to around two or three cups of tea or coffee a day, as caffeine stimulates the bowel.
• Limit alcohol and fizzy drinks.
• Reduce fatty, fried and very spicy foods if they trigger symptoms.
• Limit “resistant starch” found in processed and reheated foods, and limit fresh fruit to around three portions a day.
• Avoid sugar-free sweeteners ending in “-ol”, such as sorbitol, mannitol and xylitol, found in chewing gum and sugar-free sweets. They can cause diarrhoea and wind.
• Be physically active. Regular exercise helps bowel function, stress and mood. Yoga has some evidence for IBS specifically.

Fibre: the right kind matters

Fibre is often recommended for bowel problems, but in IBS the type of fibre matters a great deal.

• Soluble fibre, particularly ispaghula (psyllium) husk, has the best evidence in IBS. It absorbs water and forms a gel that softens hard stools and firms loose ones. Start with a small dose and increase slowly over a few weeks, drinking plenty of water.
• Insoluble fibre, such as wheat bran, can make bloating and pain worse in many people with IBS. It is generally not recommended.

Oats and linseeds (flaxseeds) are also good sources of soluble fibre. A tablespoon of ground linseeds a day, with a glass of water, can help constipation and bloating in some people.

The low FODMAP diet: what it is and how to do it properly

The low FODMAP diet is one of the most effective dietary treatments for IBS, with around half to three quarters of people reporting significant improvement in studies. FODMAP stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides And Polyols. These are types of short-chain carbohydrate that are poorly absorbed in the small intestine. They draw water into the bowel and are fermented by bacteria in the large intestine, producing gas. In a sensitive gut, this causes pain, bloating, wind and changes in bowel habit.

Examples of high-FODMAP foods include:

• Fructans: wheat, rye, barley, onion, garlic, leeks.
• Galacto-oligosaccharides: beans, lentils, chickpeas.
• Lactose: milk, soft cheeses, yoghurt (for people who do not absorb it well).
• Excess fructose: apples, pears, mango, honey, high-fructose syrups.
• Polyols: stone fruits, mushrooms, cauliflower, sugar-free sweeteners.

The low FODMAP diet is not meant to be followed forever. It has three stages:

1. Restriction (2 to 6 weeks): high-FODMAP foods are swapped for low-FODMAP alternatives. If symptoms have not improved after about six weeks, the diet is unlikely to help and should be stopped.
2. Reintroduction (6 to 8 weeks): each FODMAP group is reintroduced one at a time in increasing amounts, to find out which ones cause symptoms and how much is tolerated.
3. Personalisation (long term): a varied diet is built that includes as many FODMAP foods as possible, limiting only the specific triggers in the amounts that cause trouble.

Why the full process matters: many FODMAP foods feed beneficial gut bacteria. Staying on strict restriction for too long can reduce helpful bacteria, make the diet nutritionally unbalanced and expensive, and increase anxiety around food. Ideally the diet should be supervised by a dietitian trained in FODMAPs. Many dietitians now offer a “FODMAP gentle” approach, cutting out only the most common triggers first.

The low FODMAP diet is not suitable for everyone. People with a history of an eating disorder, those who are underweight, and people who already have very restricted diets should not start it without specialist support.

Other diets: gluten-free, dairy-free and food intolerance tests

Many people with IBS feel better avoiding wheat. In most cases this is because wheat is high in fructans (a FODMAP), not because of gluten. A gluten-free diet is not recommended for IBS unless coeliac disease has been diagnosed, and coeliac disease must be tested for before cutting out gluten, because the test only works if you are eating gluten.

Lactose intolerance can mimic or add to IBS symptoms. Reducing lactose for a trial period, or using lactose-free milk, can help some people. Hard cheeses and yoghurt are often tolerated.

Food intolerance tests sold directly to the public, such as IgG blood tests, hair analysis and kinesiology, are not reliable and are not recommended. They often lead to cutting out many foods unnecessarily.

Probiotics

Probiotics are live bacteria and yeasts marketed as being good for gut health. Evidence for probiotics in IBS is mixed, because there are many different strains and products, and studies vary. Some people find a particular probiotic helps with bloating or bowel habit. If you want to try one, choose a single product, take it at the dose recommended by the manufacturer for at least four weeks, and stop if there is no benefit. They are generally safe for healthy people, but people who are severely unwell or have weakened immune systems should get advice first.

Medicines for IBS

Medicines are chosen based on your main symptoms. Many are available from pharmacies, and others need a prescription.

For pain and cramping

• Antispasmodics such as mebeverine, hyoscine butylbromide, alverine and peppermint oil relax the gut muscle. Enteric-coated peppermint oil capsules have reasonable evidence and are widely available, though they can cause heartburn.
• Low-dose tricyclic medicines such as amitriptyline, used at much lower doses than for depression, act as “gut-brain neuromodulators”. They reduce pain sensitivity in the gut and slow transit, so they are especially helpful in IBS-D. A large clinical trial in primary care found low-dose amitriptyline improved overall IBS symptoms. Side effects can include drowsiness, dry mouth and constipation. Taking it a couple of hours before bed helps.
• SSRIs such as citalopram are sometimes used, particularly in IBS-C or when anxiety or depression is present.

For diarrhoea

• Loperamide slows the bowel and reduces urgency. It can be taken regularly or before situations where you are anxious about access to a toilet, such as a journey or meeting. Adjust the dose to avoid constipation.
• Bile acid binders such as colestyramine may help if bile acid diarrhoea is found.
• Specialist medicines such as rifaximin (an antibiotic that stays in the gut) or eluxadoline are used in some countries.

For constipation

• Soluble fibre such as ispaghula is the first step.
• Osmotic laxatives such as macrogol (polyethylene glycol) draw water into the bowel and soften stools. Lactulose is generally avoided in IBS because it can increase bloating.
• Linaclotide and other prescription medicines that increase fluid secretion in the gut can help IBS-C when laxatives have not worked.

Always read the patient information leaflet and talk to a pharmacist or nurse about how to use these medicines, especially if you take other medicines or have other health conditions.

Gut-directed psychological therapies

This is the part of IBS treatment that many people never hear about, and it is one of the most effective. Because IBS is a disorder of gut-brain interaction, therapies that calm the brain-gut pathway can reduce symptoms significantly, even in people who do not feel particularly stressed or anxious.

• Gut-directed hypnotherapy uses relaxation and imagery focused on the gut. Studies show that many people get lasting improvement in pain, bloating and bowel habit. It is now available through some health services and through app-based programmes.
• Cognitive behavioural therapy (CBT) for IBS helps people understand the gut-brain connection, change unhelpful patterns such as avoiding situations or constantly checking symptoms, and manage stress. A major trial showed that telephone and web-based CBT for IBS improved symptoms and quality of life.
• Mindfulness-based therapies and relaxation training may also help.

Being offered psychological therapy for IBS does not mean anyone thinks your symptoms are imaginary. It means using a proven treatment that works on the nervous system pathways that drive IBS.

Managing flare-ups

Even with good management, most people with IBS have periods when symptoms flare. A flare plan helps you feel in control:

• Return to simple, regular, smaller meals, and temporarily reduce your known trigger foods.
• Use heat, such as a hot water bottle or heat pad, on your abdomen to ease cramping.
• Use your antispasmodic, peppermint oil, loperamide or laxative as agreed with your healthcare provider.
• Gentle movement, such as walking, can help gas move through.
• Use breathing exercises or relaxation recordings to calm the gut-brain pathway.
• Think about what has changed: stress, sleep, illness, travel, new medicines or your menstrual cycle.

If flares are becoming more frequent, or symptoms change in nature, review your diagnosis and treatment with your healthcare provider.

IBS and women’s health

Many women notice their IBS symptoms change during their menstrual cycle, with more pain, bloating and diarrhoea around the start of a period. Hormones affect gut motility and sensitivity. Endometriosis can cause bowel symptoms that are mistaken for IBS, especially if pain is linked to periods, sex or bowel movements around menstruation. If you have cyclical pelvic pain, painful periods or pain during sex alongside bowel symptoms, ask about endometriosis. Our complete guide to endometriosis explains more.

During pregnancy, IBS symptoms may improve or worsen. Constipation is common in pregnancy. Always check medicines with a pharmacist, midwife or healthcare provider before taking them in pregnancy or while breastfeeding.

IBS in children and teenagers

Abdominal pain disorders, including IBS, are common in children and teenagers. Children may describe pain around the belly button and may not connect it to bowel movements. Stress at school, constipation and anxiety are common contributors. Parents should seek medical advice if there is weight loss, poor growth, blood in stools, night-time symptoms, fever or vomiting. Treatment focuses on reassurance, treating constipation, regular routines, and psychological approaches such as CBT and gut-directed hypnotherapy, which work well in young people.

Living well with IBS

At work

Many people with IBS hide their symptoms at work. If IBS affects your ability to work, it may help to talk to your manager or occupational health service. Reasonable adjustments could include a desk near toilets, flexible hours, the option to work from home on bad days, and breaks when needed. In many countries, long-term conditions that substantially affect daily life are covered by disability or employment protection laws.

Travel

Plan journeys with toilet stops in mind, keep to regular meal times as much as possible, take your usual medicines with you, and carry a small kit with wet wipes and spare underwear for peace of mind. Some countries offer toilet access cards for people with bowel conditions. Be careful with food and water hygiene when travelling to avoid gastroenteritis, which can trigger flares.

Relationships and intimacy

IBS can affect relationships and sex, through pain, bloating, fatigue and embarrassment. Open conversation with a partner helps. If pain during sex is a problem, talk to a healthcare provider, as there may be treatable causes.

Mental health

Living with an unpredictable gut can lead to anxiety, avoidance of social situations and low mood. These are understandable reactions, not weaknesses, and they can be treated. If you feel low, hopeless or anxious most of the time, speak to a healthcare provider.

A note for nurses and healthcare workers with IBS

Healthcare work can be hard on the gut: long shifts, irregular meals, limited toilet breaks, night work and high stress. Nurses with IBS can help themselves by planning snacks and fluids, protecting breaks, using loperamide or other medicines proactively before long shifts if agreed with their own healthcare provider, and discussing adjustments with occupational health. For nurses supporting patients with IBS, validating symptoms, explaining the gut-brain connection clearly, and signposting to dietitians and psychological therapies can make a huge difference.

Common myths about IBS

• “IBS is all in your head.” IBS is a real disorder of gut-brain interaction with measurable changes in gut sensitivity and motility.
• “If your tests are normal, there’s nothing wrong.” Normal tests are expected in IBS. They confirm that serious disease has been ruled out, not that your symptoms are imaginary.
• “Everyone with IBS should go gluten-free.” Most people react to fructans in wheat rather than gluten. Coeliac disease should be tested first.
• “You have to stay on the low FODMAP diet forever.” The restriction phase is short-term. Reintroduction is essential.
• “IBS turns into cancer.” IBS does not increase the risk of bowel cancer, though new symptoms in later life should always be checked.

The gut-brain axis: why your gut reacts to your mind

The gut has its own network of more than 100 million nerve cells, sometimes called the “second brain” or enteric nervous system. It is connected to the brain through the vagus nerve, the spinal cord, hormones and the immune system. Messages travel in both directions all the time. When you are anxious before an exam or interview and feel a sudden need to rush to the toilet, you are experiencing the gut-brain axis at work. Everyone has this connection. In IBS, the volume is turned up.

In people with IBS, research using brain scans has shown that the areas of the brain that process pain and threat respond more strongly to signals from the gut. At the same time, the brain’s ability to dampen those signals may be reduced. This means a normal amount of gas or a normal contraction of the bowel can be experienced as real pain. Over time, the brain can learn to expect discomfort, scanning the body for symptoms and reacting quickly to any sensation. This is not imagination: it is a learned pattern in the nervous system, and like other learned patterns, it can be retrained.

Understanding this helps explain why so many different treatments help IBS. Fibre and diet changes reduce the amount of gas and stretching in the gut. Antispasmodics calm the gut muscle. Low-dose neuromodulators turn down pain signalling. Hypnotherapy and CBT retrain how the brain interprets gut signals. Exercise, sleep and stress reduction lower the overall level of nervous system arousal. The best results often come from combining approaches.

Post-infection IBS

Some people can point to the exact moment their IBS began: a bout of food poisoning on holiday, a stomach bug that went round the family, or a severe gut infection that needed hospital care. After the infection cleared, the diarrhoea, urgency and pain did not fully settle. This is known as post-infection IBS. It is more likely after more severe infections, in women, in people who were anxious or stressed at the time, and in younger adults.

The good news is that post-infection IBS often improves gradually over months to years. It is treated in the same way as other IBS-D, with dietary adjustments, soluble fibre, loperamide and, in some cases, low-dose neuromodulators. Tests may be recommended to rule out ongoing infection, bile acid diarrhoea or newly triggered coeliac disease or microscopic colitis.

Conditions that can mimic or overlap with IBS

Several treatable conditions cause symptoms similar to IBS. A healthcare provider may consider them if your symptoms are not typical or are not responding to treatment:

• Bile acid diarrhoea: excess bile acids reaching the large bowel cause watery diarrhoea and urgency. It is estimated to explain a significant proportion of people diagnosed with IBS-D. It can be tested for in some countries and responds well to bile acid binders.
• Microscopic colitis: inflammation visible only under the microscope, causing watery diarrhoea, especially in older adults and people taking certain medicines such as some anti-inflammatories and acid-reducing drugs.
• Pelvic floor dysfunction: difficulty coordinating the muscles used to open the bowels can cause straining, a feeling of incomplete emptying and constipation. It is treated with specialist physiotherapy and biofeedback.
• Small intestinal bacterial overgrowth: excess bacteria in the small intestine may cause bloating and diarrhoea in some people, although testing is controversial and often overused.
• Thyroid disease: an overactive thyroid can cause diarrhoea and an underactive thyroid can cause constipation.
• Medication side effects: metformin, iron tablets, magnesium supplements, some antidepressants, opioid painkillers and many others affect bowel habit.

A sample low FODMAP day

People are often surprised at how much they can still eat during the restriction phase. A low FODMAP day might look like this, using portion sizes recommended by your dietitian:

• Breakfast: porridge made with oats and lactose-free milk or a suitable plant milk, topped with a small handful of blueberries or strawberries and a sprinkle of pumpkin seeds.
• Mid-morning: a firm banana or an orange, and a handful of peanuts.
• Lunch: rice with grilled chicken or firm tofu, carrots, courgette, spinach and peppers, flavoured with ginger, chives, herbs and garlic-infused oil (the flavour of garlic passes into oil, but the fructans do not).
• Afternoon: lactose-free yoghurt or a small piece of hard cheese with rice crackers.
• Dinner: grilled fish with potatoes, green beans and a tomato and cucumber salad, or a stew made with suitable vegetables and the green tops of spring onions instead of onion.
• Drinks: water, weak tea or coffee, peppermint tea.

Food lists are regularly updated by research teams as more foods are tested, and portion size matters: many foods are low FODMAP in small servings and high FODMAP in larger ones. A reliable app or an experienced dietitian is the best guide. In many parts of the world, traditional staple foods such as rice, maize, cassava, yam, plantain, millet and potatoes are naturally low in FODMAPs, which can make the diet easier to follow than people expect.

Eating out and social life

Social eating can be one of the hardest parts of IBS. A few strategies can help you keep enjoying meals with others:

• Look at menus in advance and choose simple dishes such as grilled meat or fish with rice or potatoes and plain vegetables.
• Ask for sauces and dressings on the side, as they often contain onion and garlic.
• Eat a small safe snack before going out so you are not very hungry and tempted to eat quickly or in large amounts.
• If alcohol triggers symptoms, alternate alcoholic drinks with water or choose lower-risk options in small amounts.
• Remember that one meal will not cause lasting harm. If you have a flare afterwards, it will settle.

Exercise and IBS

Regular physical activity is one of the most underused treatments for IBS. Clinical studies have found that people with IBS who increased their physical activity to around 20 to 60 minutes of moderate exercise three to five days a week had fewer symptoms than those who did not. Exercise helps gas move through the gut, improves bowel regularity, reduces stress and improves sleep. Walking, cycling, swimming and yoga are all good choices. People with IBS-D may prefer lower-impact activities and may want to plan exercise for times when their gut is usually calmer.

Questions to ask your healthcare provider

Appointments can feel rushed, so it helps to prepare. Consider asking:

• Do my symptoms fit IBS, and have the important conditions been ruled out?
• Which type of IBS do I have, and which treatments suit that type?
• Should I be tested for coeliac disease, bile acid diarrhoea or anything else?
• Can I be referred to a dietitian with FODMAP training?
• Is low-dose amitriptyline or another gut-brain neuromodulator an option for me?
• Is gut-directed hypnotherapy or CBT for IBS available here?
• Which symptoms should make me come back sooner?

Bring your symptom diary, a list of what you have already tried and for how long, and a list of all medicines and supplements you take.

Sleep, fatigue and IBS

Poor sleep and IBS feed each other. People with IBS often report broken sleep, and studies have found that a bad night is frequently followed by a worse gut day. Sleep loss increases pain sensitivity and stress hormones, both of which amplify gut symptoms. Protecting sleep is therefore part of IBS treatment: keep regular bed and wake times, avoid large meals and alcohol late in the evening, limit caffeine after midday, and give yourself a wind-down routine. If night-time symptoms regularly wake you, mention this to your healthcare provider, because waking from sleep with diarrhoea or pain is not typical of IBS and may need further tests.

Fatigue is also common in IBS, even with adequate sleep. It may be linked to the effort of coping with symptoms, low mood, restricted diets and, sometimes, iron deficiency. Ask for a blood test if you feel exhausted most of the time.

Frequently asked questions

Is IBS a lifelong condition?

IBS is often long-term, but symptoms usually fluctuate. Many people have long periods with few symptoms, and some find their IBS settles completely over the years, particularly with effective treatment.

Can stress cause IBS?

Stress does not cause IBS on its own, but it is a powerful trigger for symptoms because of the gut-brain connection. Reducing stress and using gut-directed therapies can help significantly.

How long does it take for the low FODMAP diet to work?

Most people who respond notice improvement within two to six weeks of the restriction phase. If there is no improvement after six weeks, the diet is unlikely to help.

Should I have a colonoscopy?

Most young people with typical IBS symptoms, no red flags and normal blood and stool tests do not need a colonoscopy. It is recommended if you have warning signs, are over the age at which bowel symptoms need investigation in your country, or are due for bowel cancer screening.

Can IBS cause weight loss?

IBS itself does not usually cause weight loss. Unexplained weight loss should be investigated by a healthcare provider.

Does IBS get worse with age?

IBS does not typically get worse with age, and many people find it improves. New bowel symptoms that start after the age of 50 should always be checked.

But what if my IBS still controls my life after trying everything?

Often, “everything” has meant cutting out lots of foods and trying several over-the-counter remedies. Many people have never been offered a properly supervised low FODMAP diet with reintroduction, a trial of low-dose amitriptyline, or gut-directed hypnotherapy or CBT. Ask your healthcare provider about referral to a dietitian and to psychological therapy for IBS, and ask whether conditions such as bile acid diarrhoea, pelvic floor problems or endometriosis have been considered. IBS can be managed, and you deserve a plan that works.

Related: IBS symptoms and diet: quick guide · Bowel cancer signs and symptoms

Sources: Rome Foundation (Rome IV criteria), World Gastroenterology Organisation global guidelines on IBS, British Society of Gastroenterology IBS guidelines, American College of Gastroenterology clinical guideline, National Institute for Health and Care Excellence (NICE), Monash University FODMAP research, ATLANTIS trial (amitriptyline in IBS), ACTIB trial (CBT for IBS).