Irritable bowel, constipation and long-lasting diarrhoea

Who is this page for?

For someone who has had cramps, bloating or an irregular bowel for months and asks themselves “is this normal?”, and for someone whose constipation and diarrhoea take turns. People rarely talk about these things out loud, and some put up with them for years without saying anything. There is no need for embarrassment. Doctors ask about exactly these things every day, and the questions are direct and respectful.

What is irritable bowel syndrome?

NIDDK describes it as a functional disorder of the digestive tract, meaning a problem with how the brain and the bowel work together. There are symptoms, but tests do not find visible damage or disease in the bowel. The main symptom is abdominal pain linked to using the toilet, together with a change in bowel movements: diarrhoea, constipation or both. NIDDK says about 12 percent of people in the United States have it. Women are affected up to twice as often as men, and it is more common under 50.

NHS lists the symptoms like this: abdominal pain and cramps that are often worse after eating and better after a bowel movement, bloating and fullness, diarrhoea with urgency, constipation, and a feeling that the bowel has not emptied. It says symptoms come and go, with good days and worse flare-ups. Mucus in the stool, tiredness, nausea and backache may also occur. NIDDK also says the exact cause is not known and several factors play a part: stress and difficult childhood events, depression and anxiety, an earlier digestive infection, sensitivity or intolerance to certain foods, and genes. So saying “it’s just nerves” is only half the story, and the discomfort is real.

NHS names alcohol, caffeine, spicy and fatty food, stress and frequent antibiotic use as possible triggers of flare-ups. This list is not the same for everyone, and sometimes flare-ups appear for no reason.

Who should look into it?

NHS says that if symptoms last more than four weeks, it is better for a doctor to examine you and request the necessary tests. The doctor asks about the pattern of the symptoms, how long they have lasted, and how they relate to food. The doctor may also feel your abdomen. NHS says writing down symptoms before the visit helps you remember. The symptom diary is for this.

It is important to know that there is no specific test for irritable bowel syndrome. NHS names a blood test for coeliac disease and a stool test for infection and inflammatory bowel disease, and says hospital tests are usually not needed unless the doctor does not know the cause. The ACG abstract also suggests, for patients with diarrhoea, a blood test for coeliac disease and a stool test to rule out inflammatory bowel disease, and says the diagnosis can be made from the pattern of symptoms, not only by excluding all other diseases. Which tests you need is up to your doctor. The same goes for the decision about a colonoscopy, which, if it is needed, is made according to your age, symptoms and family history.

Constipation

NHS describes constipation as a change in bowel habit: fewer than three bowel movements a week, hard or lumpy stools, straining or pain, and a feeling of not emptying. The causes are common and usually simple: too little fibre or fluid, little physical activity, putting off going to the toilet, a change in food or routine, some medicines, stress or depression. It is more common in older people and in pregnancy. NHS says conditions such as diverticulosis (small pouches in the bowel wall) or bowel cancer can also be causes, but this is rare.

What helps (NHS):

• Increase fibre gradually (oats, bran, linseed), and fruits such as apples, apricots, grapes, raisins, raspberries and strawberries, which help soften the stool.
• Drink plenty of fluids.
• Walk daily.
• Try to go at the same time and place each day, without rushing. When you feel the urge, do not put it off. Resting your feet on a low stool, so your knees sit above your hips, also helps.
• Improvement may take from a few days to a few weeks.

A pharmacist can suggest a laxative if needed. NHS says most laxatives work in about three days and should be used for a short time. If you take a medicine that causes constipation, do not stop it yourself. Talk to your doctor.

If constipation goes on for a long time, hard stool can sometimes get stuck in the rectum and liquid leaks around it. NHS says a doctor or nurse should treat this, and you should not try to remove it yourself.

Diarrhoea

NHS says the cause of diarrhoea is mostly an infection or food poisoning, which usually clears within 5 to 7 days. But diarrhoea can also come from medicines, intolerance to certain foods, irritable bowel syndrome, anxiety, inflammatory bowel disease, coeliac disease and other conditions. Diarrhoea that lasts longer than a week deserves a check.

Care at home (NHS): rest and drink plenty of fluids, in small sips if you feel nauseous. Eat whenever you can. Avoid fatty and spicy food. Fruit juice and fizzy drinks may make diarrhoea worse. Wash your hands often. Stay at home until two days after the diarrhoea and vomiting have stopped.

Take dehydration seriously. NHS names dark, strong-smelling urine or passing less urine than usual as signs. NHS says that if you are elderly, have a weak immune system or have another illness that raises the risk of dehydration, you should talk to a pharmacist or doctor sooner. In a child under 5, signs of dehydration are a reason for urgent medical attention.

Bowel changes that should not be put down to “irritable bowel syndrome”

Most constipation and diarrhoea is not a sign of anything bad. But there are some signs that NHS and WHO want a doctor to see, because they may point to another condition, including inflammatory bowel disease or, rarely, bowel cancer:

• Blood in the stool or bleeding from the anus. Haemorrhoids and anal fissures are common causes, and a small one-off amount is not usually serious. But do not diagnose it yourself. Show bleeding that comes back to a doctor soon, and do not wait for three weeks to pass.
• Black or dark red stool, or bloody diarrhoea.
• Stools that are looser, thinner or longer than usual for three weeks (NHS).
• Unexplained weight loss.
• Pain or a lump in the abdomen, more tiredness than usual, paleness or shortness of breath, which can be a sign of anaemia (NHS).
• A sudden change in bowel habit that does not fit your history. NHS lists it among the reasons to see a doctor, and WHO counts older age and family history among the risk factors for bowel cancer.

WHO points out that in the early stages bowel cancer has no symptoms or only mild ones. For this reason a doctor sometimes talks with you about screening even without symptoms, depending on your age and family history. Read the details on the page Crohn’s and colitis, blood in the stool and bowel screening.

What does treatment look like?

Treatment is based on the main symptom. NHS starts with lifestyle changes: a balanced diet and a food and symptom diary to identify triggers, about 1.5 litres of fluid a day (water or caffeine-free drinks), soluble fibre (oats, linseed), which may improve bloating and constipation, cutting down on wholegrains, nuts and high-fibre seeds if you have diarrhoea, avoiding the sweetener sorbitol, exercise, relaxation, and regular, unhurried meals. NHS says you can try probiotics for about a month. Then, if that is not enough, the pharmacy has medicines for abdominal cramps, diarrhoea or constipation; the pharmacist or doctor tells you which type to use and for how long. If you have had to cut out many foods or simple treatments do not work, see a doctor, who may refer you to a dietitian or a specialist.

The ACG abstract also suggests psychological therapy focused on the brain-gut connection to reduce overall symptoms. This does not mean the discomfort is “made up”. It targets the same brain-gut connection that NIDDK lists in the mechanism of this condition.

Do not keep to strict food restrictions for a long time. NIDDK says you may need to change your food for a few weeks to see whether it has an effect, and it is best to go ahead with a dietitian. Any restrictive diet should be followed with the advice of a doctor or dietitian. See also the food and habits guide.

If your doctor suggests nutrition or psychological counselling, the patient support section introduces the related services.

When to act urgently

Call 115 (Iran’s emergency number) right now (NHS): anal bleeding that does not stop, or a lot of blood and large clots when passing stool, vomiting blood or what looks like coffee grounds, sudden severe abdominal pain, confusion or unresponsiveness.

See a doctor or go to the emergency department the same day (NHS): black or dark red stool, bloody diarrhoea, being unable to keep fluids down, signs of dehydration that do not go away with drinking fluids, diarrhoea that has lasted more than 7 days, repeated bleeding from the anus, a lot of unexplained weight loss, a hard lump in the abdomen, or shortness of breath and palpitations with paleness.

Book an appointment soon: bowel symptoms lasting more than four weeks, a change in bowel habit that has lasted three weeks, or symptoms that do not improve with simple changes.

See the full list in urgent signs.

This page is for information and does not replace an examination.