What is diarrhoea?

Diarrhoea is the passing of loose or liquid stools more than three times a day, or more frequently than is normal for you.

Sometimes diarrhoea is mixed with mucus, pus or blood, and a feeling of needing to rush to the toilet urgently. Diarrhoea is sometimes passed very rapidly, so can be called explosive. It may also lead to bowel incontinence with leakage of stool. Our guide on bowel incontinence has more information about this and ways to manage it.

Diarrhoea happens when the intestines cannot absorb all the nutrients or fluid produced during the digestive process. After the small intestine absorbs useful nutrients from what we’ve eaten, the liquid and non-digestible parts of food pass into the colon. Most of the water is normally absorbed here, and the leftover waste formed into solid stools. These collect in the last part of the colon and the rectum until they are passed out of the body in a bowel movement.

However during a Crohn’s or Colitis flare-up, the cells in the lining of the intestine become inflamed, meaning the intestine can’t absorb all the nutrients and fluid. This results in stools being loose and watery, or even entirely liquid, causing diarrhoea. The looser faeces can also move more rapidly through the colon, causing more frequent bowel movements.

• Side effects of IBD medicines - Aminosalicylates (5-ASAs) such as mesalazine and sulfasalazine can cause diarrhoea. Taking the tablets with or after food may reduce this side effect. Some immunosuppressants, such as azathioprine and methotrexate, can also cause diarrhoea, especially during the early weeks of treatment. Talk to your doctor or IBD team about ways to manage this, or see our medicines guides, Aminosalicylates (5-ASAs), Azathioprine and Methotrexate for more information.

• Side effects of other drugs - Check whether diarrhoea is a side effect of any other medications you are taking. For example, acid-lowering treatments, such as omeprazole and lansoprazole, and antibiotics can also cause diarrhoea.

• Colectomy and ileo-rectal anastomosis – During this operation the colon is removed, and the end of the ileum (the last part of the small intestine) is joined directly to the rectum. After this procedure your stools will tend to be much more liquid because you no longer have a colon to absorb the water. Our guides Surgery for Crohn’s Disease and Surgery for Ulcerative Colitis have more information on what to expect. 

• Small bowel surgery for Crohn’s Disease - If you have had the end of your ileum removed, you may experience bile salt diarrhoea. Bile salts are produced in the liver and are usually reabsorbed in the ileum, so that only very small amounts enter the colon. However, if part of the ileum is inflamed or has been removed, much higher levels of bile salts pass into the colon. This draws water into the colon, causing watery diarrhoea.

• Malabsorption of fats - If you have Crohn’s in the ileum you may have difficulty absorbing fats. This can lead to urgency and stools that are pale, bad smelling and oily – they therefore float and can be difficult to flush away.

• Iron supplements - You may be prescribed iron supplements if you experience anaemia caused by your Crohn's or Colitis. A change in bowel habit is a common side effect of iron supplements and while some people get constipation, others get diarrhoea. They may also make your stools very dark in colour.

• Irritable Bowel Syndrome (IBS) - IBS is sometimes confused with Inflammatory Bowel Disease, but is a different condition. Like Crohn's and Colitis, IBS can cause abdominal pain, bloating, and bouts of diarrhoea or constipation. However, it does not cause inflammation of the bowel or bleeding. Some people with Crohn’s or Colitis develop IBS-like symptoms. They might, for example, have diarrhoea even when their Crohn's or Colitis is inactive. These symptoms may need specific treatment as well as their usual Crohn's or Colitis medicines.

• Diet and food sensitivities – Certain foods can have a laxative effect, such as: fibre-rich food, spicy food, chocolate, caffeine, alcohol, fructose (a sugar in fruit) and sorbitol (an artificial sweetener). Some people also find that certain foods such as wheat and dairy products can trigger symptoms or make them worse, and that by reducing these in their diet, their diarrhoea improves. If you are concerned about your diet or food sensitivities, your IBD team may be able to refer you to a dietician. It is important to get advice from a qualified dietician before making any major changes to your diet so as not to miss out on important nutrients.

• Infections - Diarrhoea can often be a sign of infections such as gastroenteritis, food poisoning, or clostridium difficile (C. diff). Your doctor or IBD team may carry out tests to make sure your diarrhoea is not due to such infections.

• Stress – Anxiety or stress can cause diarrhoea, and stress has been found to be a risk factor for an Ulcerative Colitis flare-up. The evidence is less clear for Crohn’s, although many people feel stress does have an impact on the activity of their Crohn’s.

• Antidiarrhoeals – These slow down the contractions (muscle movements) of the bowel, so that food takes longer to pass through your gut. This allows more fluid to be absorbed from the bowel into the body, which results in firmer stools that are passed less often. Loperamide (Imodium) is a commonly used and effective antidiarrhoeal drug. Always ask your IBD team before taking antidiarrhoeals. If taken during a severe flare-up, this can occasionally lead to a serious complication called toxic megacolon. You may not be able to take antidiarrhoeals if you have a narrowing of the bowel called a stricture.

• Antispasmodic drugs - These reduce the muscle movement in the bowel, which relieves diarrhoea as well as the cramping pain which can occur when the intestinal muscle is contracting too strongly. Brands include Buscopan and Colofac. They are usually safe to take, but check with your doctor first.

• Bile salt drugs - These include colestyramine (Questran) and colestipol (Colestid) which come in powder or granule form, and colesevalam (Cholestagel), which comes as tablets.

These bile salt drugs absorb the overflow bile salts, preventing them from reaching the colon and causing diarrhoea. They can affect the absorption of other drugs, so if you are taking other medicines, it is important to check with your IBD team or pharmacist about how to manage taking them alongside each other. The patient information leaflets for these drugs also have specific information about recommended timings. Some people experience constipation with these medicines, so you may want to try changing your dose until you find the right amount for you.

• Bulking agents - Bulking agents or ‘bulk formers’ are made from plant fibres. These include ispaghula (Fybogel) and sterculia (Normacol), which come as granules. This thickens liquid stools and softens hard stools, providing the bulk needed for the bowel to work more normally. Bulking agents are most commonly used for constipation but some patients also find them helpful in regulating diarrhoea as they absorb water. You should talk to your pharmacist or doctor before taking these, and avoid bulking agents if you have a stricture (narrowing) of the bowel.

You can find further information on all these types of medicines in other treatments.

Eating

• Eat small, regular meals, rather than large meals with a long time between them.

• Keep a food diary, like the example shown in our information on food. Record everything you eat and note any symptoms you experience afterwards, such as diarrhoea, bloating and wind. Once you have identified any foods causing you problems, you can think about ways to avoid them. Some sensitivities might be only temporary and you may be able to re-introduce that food at a later date. If you are finding it difficult to keep a balanced diet, ask your IBD team if they can refer you to a dietician.

• Be mindful of gluten sensitivity. If your diarrhoea is worse after eating foods containing gluten (a protein found in wheat, barley and rye) it may be due to a gluten sensitivity. You can try reducing gluten-containing foods in your diet such as bread, pasta and cake, to see if this helps. Information about which foods contain gluten, which items are gluten-free and where to get them, is available at coeliac.org.uk. Sometimes, gluten sensitivity is a sign of coeliac disease. You can ask your doctor for a blood test to check for this. 

• Avoid spicy and fatty foods if they make your symptoms worse.

• Limit your fibre intake as high-fibre foods can make your diarrhoea worse. During flare-ups, it might help to reduce the amount of fibre you eat, such as wholegrains, nuts, seeds, and the types of fruit and vegetables usually eaten with skins, pips and seeds. Fibre is an important part of the diet, as it helps the bowel to function normally, so talk to your IBD team or dietician before making changes to the fibre in your diet. You can try adding fibre back into your diet once your flare has settled.

• Pay attention to how dairy affects you. If dairy products make your diarrhoea worse, you may be intolerant to lactose. It is also possible to develop a temporary intolerance during a flare-up. Lactose is a sugar found in foods such as milk, cream and cheese. Milk and dairy products are an important food group, so you should talk to your IBD team or dietician before removing them from your diet. Your IBD team can also help you find out if you are lactose intolerant. Symptoms can be managed by following a low lactose or lactose-free diet, and using lactose-free products instead. Some medicines also contain lactose, but do not stop taking any prescribed medication without checking with your doctor or IBD team.

• Some people have found certain diets and meals helpful when experiencing diarrhoea, such as the BRAT diet (bananas, rice, applesauce and toast), and chicken and rice soup. These foods are not high in fibre so don’t stimulate the bowel muscles to contract as much, and rice in particular may have an absorbent affect, reducing the water content of the stool. However, these diets do not contain enough nutrients to be healthy long-term options. It is best to avoid extreme exclusion diets without first getting advice from a qualified dietitian to make sure that you are still getting a balanced and nutritious intake.. For more information on healthy eating with Crohn’s or Colitis see our guide on food.

Drinking

• Many people are sensitive to caffeine, so try opting for decaffeinated coffee, tea, and other drinks.

• You may wish to reduce your consumption of alcohol, as this can have a laxative effect.

• Fizzy drinks and drinks made with artificial sweeteners such as sorbitol can also cause diarrhoea.

• Plain water or squash is generally a good option.

For more serious dehydration your doctor may recommend drinking an Oral Rehydration Solution (ORS) with a higher sodium (salt) level. For more details on this and how to avoid and manage dehydration, see our information on dehydration.

Another way of managing urgency is practising pelvic floor exercises to strengthen the muscles around your rectum and anus to improve bowel control. More information about bowel retraining and pelvic floor exercises can be found in our information, Bowel incontinence.

The Crohn’s & Colitis UK ‘Can’t Wait Card’ can help you get access to toilets without embarrassment or confusion. The card is also available in different languages for use when travelling abroad. We also offer new members a RADAR key which gives you access to over 9,000 locked public toilets around the country. For more information visit crohnsandcolitis.org.uk/membership. You might also find it helpful to look at the Great British Public Toilet Map: greatbritishpublictoiletmap.rca.ac.uk.

• Using moist toilet paper, damp cotton wool or moist toilet wipes can be more comfortable than dry toilet paper. Some baby wipes contain alcohol and other chemicals which can irritate the skin, so try and opt for alcohol-free brands or those for sensitive skin.

• Whenever possible, wash around the anus after a bowel movement. If you don’t have access to a bidet, you could use a shower attachment over the edge of the bath. Some people find a jug filled with warm water makes washing easy on the toilet. You could also use a soft disposable cloth with warm water, but avoid flannels and sponges as they can be rough and are difficult to keep clean. Avoid using disinfectants or antiseptics in the washing water as these can sting and you may be sensitive to the chemicals in them. Plain warm water is best.

• Avoid using products with strong perfume and instead use non-scented soap or a no-rinse cleanser. These cleansers avoid the need for soap and water, which may dry the skin. Ask your doctor or IBD team about these.

• When drying the area with soft toilet paper or a soft towel, be very gentle and pat rather than rub. If you are very sore, you could try using a hairdryer on a low heat setting.

• Barrier products can be used to protect the skin from faeces are available in different forms such as creams and wipes. Check with your doctor or nurse before using these products, as some people are allergic to components of some products such as lanolin, a natural wax with moisturising properties. Barrier creams should be used a little at a time, as too much can stop the skin from breathing and can make the area sweaty and uncomfortable. Always make sure the old layer is washed off before applying more. Other products that people have found helpful include Sudocrem, Metanium and zinc and castor oil cream.

• Avoid scratching as this will make the area more painful. If you find you are scratching at night, you could try wearing cotton gloves in bed (available at some pharmacies).

• Try to allow the air to get to the area.

• If you use incontinence pads, try to make sure that no plastic touches your skin, and you use pads with a soft surface. A Continence Nurse can advise you on which pads are best for you – you can ask your doctor or IBD team to refer you to a Continence service.

• Some people find certain food or drink makes them more likely to experience soreness. It might be worth cutting down on these on a trial basis, but you should seek advice from your IBD team before doing this.

• Wearing cotton underwear and avoiding synthetic material will allow the skin to breathe. It is best to avoid tight jeans and other clothing that may rub the area. Instead of tights you could try stockings or crotchless tights.

If you continue to feel sore or your skin is broken, talk to your doctor or IBD team. There are other products that can be prescribed to help heal the sore skin, or you may have an infection (such as thrush) that needs specific treatment.

There are various deodorising products designed for people with a stoma, including sprays such as Auricare Odour Eliminator, Salts Odour Eliminating Spray and Limone. Other types of deodorising products include OstoMIST Pouch Odour Neutralising Drops, Morform sachets (a gelling agent to manage very liquid output, which also reduces odour) and Brava Lubricating Deodorant, designed to make it easier for output to go to the bottom of the bag, while masking smells.

Some deodorising products are only available on prescription, so you might want to speak to your stoma nurse about the products available.

• Irritable Bowel Syndrome (IBS) - Some people with Crohn's or Colitis experience IBS-like symptoms, which include constipation and/or diarrhoea.

• Low-fibre diet – Fibre helps stools pass through the bowel, so if you have reduced your intake of fibre, you may find that you become constipated. Excess fibre should be avoided if you have a stricture of your intestine, as can occur in Crohn’s Disease.

• Low fluid intake – If you are not drinking enough, this can lead to constipation as the stools become hard, dry and difficult to pass.

• Drugs – Constipation can be a side effect of some drugs, for example, anti-diarrhoeals, iron supplements and painkillers such as tramadol and co-codamol.

• Damage to the anal muscles – A common cause of constipation in women following vaginal childbirth or pelvic surgery.

• Drink more fluids - You may find that drinking plenty of fluids helps form softer stools that are easier to pass. It may help to cut down or avoid caffeine and alcohol.

• Increase your fibre - It may also help to increase the amount of fibre in your diet, although this is not advisable for people with strictures, which are narrowings of a section of the bowel due to bowel wall thickening, inflammation or scarring. Talk to your IBD team or dietician before changing your diet, especially if you have a stricture.

• Increase your exercise - If you can, increase the amount of exercise you do, as this can help to increase the speed at which stools move through your colon.

• Bulking agents - Some people may find that bulking agents, such as Fybogel or Normacol, can soften hard stools. Again these may not be suitable if you have a stricture, so you should talk to your IBD team before trying these.

• Laxatives - Laxatives can help to relieve constipation. Osmotic laxatives are usually considered the best type of laxative for people with Crohn’s or Colitis. They include lactulose and macrogol. Osmotic laxatives increase the amount of water in your bowel to make your poo softer and easier to pass. Laxatives can cause diarrhoea, wind and stomach cramps, especially at the start of treatment.

Many of the companies that make these medicines recommend that they are not used in people with acute or severe Crohn’s or Colitis. Your doctor or nurse may have prescribed these for you. If so, they will have considered the advantages and disadvantages of you taking them. Speak to your IBD team before trying laxatives or if you have any concerns about taking them.

If you are worried about constipation and how to treat it, speak to your doctor.

Some people with constipation may develop haemorrhoids (also known as piles). Haemorrhoids are swellings that contain enlarged blood vessels, found inside or around the anus. Symptoms can include:

• Bleeding after passing a stool
• Itchiness around the anus
• Lumps around the anus
• Pain or discomfort when passing a stool
• Soreness, redness or swelling around the anus

Symptoms often clear up on their own, or by using treatments available from a pharmacy. If constipation is the cause of your haemorrhoids, lifestyle changes such as increasing fibre, fluids and exercise may help prevent them (see How can I treat constipation?) You may find improving your toilet routine also helps, by taking simple measures such as not ignoring the urge to pass stools, and not straining on the toilet. To relieve any discomfort you may experience when going to the toilet, see the section How can I manage sore skin?

If these steps don’t work for you, speak to your doctor, who may need to refer you to a specialist.

Anal fissures

Constipation can cause anal fissures. These are small tears or open sores in the lining of the anal canal. They are most commonly caused by constipation, when a very hard or large stool tears the lining of the anal canal. Symptoms include:
• A sharp pain when you pass stools, often followed by a deep burning pain that may last several hours
• Bleeding when you pass stools – you may notice a small amount of blood
either on your stools or on the toilet paper

If you think you have an anal fissure, see your doctor. Most anal fissures get better within a few weeks without treatment, but they can recur if constipation persists.

See the section How can I treat constipation? for self-help measures you can also use to prevent anal fissures. Again, delaying going to the toilet should be avoided, as this can make stools harder and drier, and more likely to cause an anal fissure. To relieve any pain or discomfort, you can try taking paracetamol, or soaking your bottom in a warm bath several times a day, particularly after a bowel movement. See the section How can I manage sore skin? for tips on how to gently wash the area. Your doctor may prescribe medication to help relieve symptoms and speed up the healing process.