Changes in bowel habits

Lymphoma, and some of the treatments for lymphoma, can cause changes in bowel habits: diarrhoea, constipation and flatulence. Although these tend to be temporary and mild, any change in bowel habit can be distressing. On this page you can find practical advice to help you cope with changes in your bowel habits.

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Changes in bowel habits
Flatulence (passing wind)
Resources and useful organisations

Here we give general guidance on coping with diarrhoea, constipation and flatulence. Always seek advice from your medical team if your bowel habits change. They can give you advice tailored to your individual situation, which may include tweaking or changing your medication. If you have another bowel condition (eg Crohn’s disease or ulcerative colitis), haemorrhoids or an anal fissure, you should discuss this with your medical team as they will take this into account in the advice they give you.

Note: You might have heard that probiotic (or ‘bio’) yoghurts and drinks can improve your digestive health. It might be the case, but the evidence is inconclusive. In any event, it is important that you avoid probiotics if you have a weakened immune system, which includes being neutropenic (having a low number of a type of white blood cell called a ‘neutrophil’). Consumption of probiotics by people with a weakened immune system could lead to sepsis, which can be life-threatening.

Changes in bowel habits

Bowel habits can change for various reasons:

Sometimes changes in bowel habits occur when you begin treatment. When they occur as a side effect of chemotherapy, the changes might return soon after starting each cycle (block) of treatment. They tend to reduce and clear during each cycle of chemotherapy. Changes in bowel habits are usually temporary and mild, but they can be longer lasting.

Speak to your medical team if you are affected by any changes in your bowel habits. Although you might feel embarrassed, health professionals are used to such conversations and will try to put you at ease. It is important that your doctor or nurse is able to assess the cause of your symptoms and check for any signs of infection that may need treatment. They can offer you advice on how best to manage your symptoms and may prescribe medication if necessary. Getting help early can make it much easier to treat changes in bowel habits and may even avoid a hospital admission.

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Diarrhoea means passing looser, more watery stools (poo) more frequently or in larger amounts than is usual for you. In this section, we list the common symptoms and give general advice to help you cope with diarrhoea.

Symptoms of diarrhoea

As well as the change to your stools described above, symptoms of diarrhoea include:

  • abdominal (stomach) cramps
  • needing to go to the toilet urgently or suddenly
  • feeling bloated
  • feeling sick
  • fever (in adults, this is a temperature above 37.5°C).

You must tell your doctor straightaway if you have any of the following symptoms:

  • blood in your stools
  • very dark brown or black stools
  • persistent stomach ache
  • severe stomach ache
  • persistent vomiting (throwing up) 2–3 times a day
  • weight loss
  • dehydration (dark yellow urine is a sign of dehydration)
  • painless passing of a lot of watery diarrhoea.

Coping with diarrhoea

Having diarrhoea takes up a lot of energy. Where possible, ask friends and family to help with chores around the house to allow you to rest. Your doctor might prescribe antidiarrhoeal medicines to help manage your diarrhoea. You can also try some simple things to ease your diarrhoea, lower physical discomfort and reduce embarrassment. These include making some temporary changes to your diet, soothing sore skin, increasing your comfort at home and planning ahead before you go out and about. Smoking can stimulate the bowel and worsen diarrhoea, so it is best avoided.

Medication for diarrhoea

You may be prescribed antidiarrhoeal medicines. Always seek medical advice before taking such medicines. Diarrhoea might be directly linked to your treatment but it could also be a symptom of an infection or virus. Antidiarrhoeal medicines are not the right treatment for all types of diarrhoea. Their suitability depends on the cause and taking antidiarrhoeal medicines inappropriately could lead to sepsis.

Antidiarrhoeal medicines fall into 2 main groups:

  • anti-motility medicines, eg Ioperamide (Imodium®). They lower your number of bowel movements and reduce how often you need the toilet.
  • bulk-forming agents, eg methylcellulose (Celevac®). They make your stools more solid.

These medicines are often given alongside oral rehydration solutions (ORSs), eg Dioralyte®. Your body needs the right balance of water and mineral salts to prevent dehydration. ORSs help to replace the water and mineral salts you lose through diarrhoea. They come as sachets containing powder that dissolve in water. You can buy ORSs in pharmacies, chemists, supermarkets and online without a prescription.

Changes to your diet

Your diet can have an effect on how your bowel works. Making some temporary changes to what you eat and drink could help to manage your diarrhoea. Always discuss with your medical team before making any changes. Below are some suggestions you may like to ask them about.


It is important to drink extra fluids to replace those lost through diarrhoea. Aim for at least 2 litres of liquid each day, sipping little and often. Drinks that stimulate the bowel can make diarrhoea worse. Instead, choose ones that help to replace lost fluids, sugars and minerals.

Drinks that might help

  • Plain water or water mixed with weak squash
  • Water mixed with soup broth
  • Oral rehydration solutions (ORSs)

Drinks to avoid

  • Fruit juices
  • Caffeinated drinks
  • Very hot or very cold drinks
  • Fizzy drinks (including beer)
  • Alcohol
  • Milk


You might not feel like eating very much if you have diarrhoea. Generally, doctors say it’s OK not to eat for a little while if you don’t feel up to it. You should begin eating solid foods again as soon as you feel able to. Rather than having 3 main meals, you may find it more manageable to eat smaller snacks more frequently throughout the day.

Foods that might ease diarrhoea

  • Low fibre foods, eg potatoes, white rice, dry white toast, soup, peeled and boiled vegetables
  • Potassium-rich foods, eg bananas, potatoes, fish, bread, chicken, beef, turkey

Foods to avoid

  • Fatty, greasy foods 
  • Spicy foods
  • Dairy products
  • High-fibre foods, eg raw fruit and vegetables, beans, nuts, wholegrain cereal

Soothing sore skin around your anus

Diarrhoea can make the skin around your anus (back passage) sore and tender. There are ways to help soothe the skin in this area.  

  • Wash your bottom instead of wiping it if it is very sore.
  • Use fragrance-free toilet wipes. These are softer than toilet paper. Unlike baby wipes, they can be flushed down most toilets.
  • Have a warm bath to ease pain and tenderness.
  • Pat the area dry with a soft towel after a bath or shower. This is gentler on your skin than rubbing.
  • Apply a soothing cream. Ask a member of your medical team to recommend one.
  • Wear breathable, cotton underwear and fairly loose clothing to help to reduce irritation.

Coping when you are out and about

Being out and about can be stressful if you have diarrhoea. You may wish to avoid long journeys. If this is not practical, planning ahead can help you to feel more confident and better prepared. Depending on your personal circumstances, you may find it helpful to take one or more of the following precautions:

  • Take a body spray and flushable wipes with you to help you feel fresh.
  • Locate toilets. Plan ahead before you travel so that you know where you’ll find toilets.
  • Carry spare clothes and a plastic bag in case of soiled clothes.
  • Wear a disposable waterproof pad (sanitary towel or incontinence pad) to protect your underwear. You can buy these from pharmacies, chemists, supermarkets, or online. It may also be worth asking if your hospital have a supply.
  • Carry a Just can’t wait card produced by the Bowel and Bladder Community. The card states that you have a medical condition and need to use the toilet urgently. More information about the Just can’t wait card and how to get one is available on the Bladder and Bowel Commnity’s website.

Feeling comfortable at home

If you have diarrhoea, you might feel more relaxed at home than when you are out and about. Consider any changes you could make to further increase your comfort. Depending on your personal circumstances, you may find it helpful to take one or more of the following precautions:

  • Wear bottoms that are easy to remove quickly – clothing that doesn’t have fiddly zips, buttons or other fastenings (eg jogging bottoms) can be helpful if you have to go to the toilet urgently.
  • Use a mattress protector – if you are worried about having an accident in the night, a mattress protector or plastic sheet can prevent damage to your bed and make cleaning easier.
  • Wear disposable pads –wearing a pad could help you to feel more relaxed, especially when you are trying to sleep.
  • Speak to your medical team if you are worried about not making it to the toilet in time. They may be able to change or tweak your medication to help the situation. If your diarrhoea is very severe, you could talk to them about having a commode by your bed.

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Constipation means being unable to go to the toilet regularly to pass stools, or being unable to completely empty your bowel. Stools might be small and hard if you are constipated and passing them may cause you to strain. Many doctors class constipation as passing stools fewer than 3 times a week. However, the meaning of ‘regular’ varies from person to person and depends on what is normal for you.  

Symptoms of constipation

As well as difficulty passing stools, symptoms of constipation include:

  • abdominal (stomach) cramps
  • a hard, swollen stomach
  • feeling bloated
  • feeling sick
  • headaches
  • loss of appetite
  • pain when going to the toilet to open your bowels
  • liquid diarrhoea that you can’t control (‘overflow diarrhoea’).

Constipation is a side effect of some chemotherapy drugs, antiemetics (anti-sickness medications) and painkillers (especially morphine-based ones, such as codeine). Ask your medical team whether this is a potential side effect of any of the medication you have been given.

Seek medical advice if you have not opened your bowel for a day or 2 longer than is usual for you. Early treatment is often much simpler than if you leave it longer.

Coping with constipation

Simple dietary and lifestyle changes, such as taking light exercise, can help if you are constipated. We offer some general tips below. Speak to your medical team for the best advice according to your individual situation. If necessary, your doctor might prescribe medication.

Medication for constipation

Speak to your medical team if you are constipated. Although you might feel awkward discussing it, they are used to such conversations and will be able to help. Very often, medication for constipation is not needed but adjusting other medicines you are taking could help. Ask your medical team for advice.

Treatments for constipation include:

  • Laxative drugs, which soften stools and make them easier to pass by triggering bowel movements. Laxatives are taken in a tablet, liquid or capsule form. You can buy laxatives in pharmacies, chemists, supermarkets and online without a prescription.
  • Suppositories, which are small pellets that contain medicine. These are inserted into your rectum (back passage), where they encourage the passing of stools.
  • An enema, which is a liquid that is inserted into the rectum causing the bowel to empty. Enemas tend only to be used in severe cases.

The above interventions may not be appropriate at certain times during your treatment, especially if your blood counts are low. It is therefore important that you seek medical advice before starting one.

Changes to your diet

Your diet can have an effect on how your bowel works. Making some temporary changes to what you eat and drink could help to manage constipation. Always discuss with your medical team before making any changes. Below are some suggestions you may like to ask them about.

Eating and drinking

Food and drinks that act as natural laxatives can prevent, reduce or stop constipation. Eating foods that are high in soluble fibre (a type of fibre that can be digested by your body) can help to make your stools softer and easier to pass. Eating at the same time each day can encourage regular bowel movements. It’s also important to drink plenty of fluids if you’re constipated. Aim for at least 2 litres a day. 

Foods rich in soluble fibre include:

  • cereal, eg oats, barley and rye
  • fruits, eg oranges and apples
  • root vegetables, eg carrots and potatoes
  • golden linseeds.

Foods and drinks that act as natural laxatives include:

  • fruits that are high in sorbitol (a type of sugar), including oranges, apples, prunes and raspberries
  • liquorice
  • coffee.


When you need to go the toilet, go as soon as you can – waiting can make constipation worse. Try passing stools in the morning or around half an hour after meals. Hurrying, or feeling as though you do not have privacy can also worsen constipation. Think about how you can make improvements if you feel that time and lack of privacy could be affecting you.

Although living with lymphoma and the side effects of treatment can make it more difficult to keep active, even taking light exercise, such as a gentle walk, can help to keep your stools soft and regular.

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Flatulence (passing wind)

Flatulence helps to release the gases that build up in your digestive system. When you eat or drink, you swallow small amounts of air, which gathers in your digestive system. Gas is also produced during the process of digestion. As well as passing wind more frequently than is normal for you, symptoms of flatulence include feeling full and bloated.

Some treatments for lymphoma can create excess gas in your digestive system and lead to increased flatulence. While this isn’t a serious medical problem, it can be embarrassing and uncomfortable. Below, we give some tips to help reduce flatulence. Speak to your medical team if flatulence is bothering you. There are some medicines that might help.

Tips to help reduce flatulence

  • Eat and drink slowly and chew your food well. This reduces the amount of air you swallow.
  • Eat smaller meals more frequently during the day as this can help with digestion.
  • Add ginger to your diet or try drinking peppermint tea or fennel tea. You may find that these aid digestion.
  • Take gentle exercise, which can help improve digestion and bloating.

There are also things you can avoid in order to reduce flatulence. Smoking can worsen flatulence, as can some foods and drinks. These include: cabbage, sprouts, onions, beans, cauliflower and fizzy drinks (including beer and pop, such as lemonade). Eating large amounts of high-fibre foods (including wholemeal bread, bran, cereals, nuts and seeds) can also have an effect, so you could try lowering how much of these types of food you eat.

Medicines for flatulence

If your flatulence is very bothersome, the following medicines might help:

  • Charcoal tablets, which soak up gas within the digestive system and can also help to absorb unpleasant smells from passing wind.
  • Simethicone, which treats symptoms of flatulence such as fullness and bloating.

These medicines are available over-the-counter; however, you should always seek advice from your doctor before taking them. This is particularly important if you are on treatment for lymphoma because it is possible for medicines to interact with one another in unwanted ways.

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