Bowel changes after treatment

Treatment for bowel (colorectal) cancer can cause changes to how your bowels work. Changes can include how often you poo, how urgently you need to go, and difficulty emptying your bowel completely.

These effects usually improve in the weeks and months after you finish treatment. But sometimes they might go on for longer and can be difficult to live with. There are things you can do to help you manage these changes.

The bowel changes you have after treatment will depend on a number of factors. These include what operation you have, which part of your bowel the surgeon removes and any other treatments you have.  Your doctor or nurse will tell you more about what to expect after treatment and help you manage any bowel changes.

How treatment affects your bowel function

The changes to your bowel function will depend on what treatment you have. Side effects are likely to be worse if you have a combination of treatments.

Surgery to the large bowel (colon)

The body absorbs water from undigested food as it passes through the colon. The waste material (poo) is then stored in the back passage (rectum) until you pass it out of the body through your anus. Straight after surgery to remove part of your colon, your poo might be a bit looser and more frequent. But this usually settles down after a few weeks and medicines may help with some of the symptoms.

Surgery to the back passage (rectum)

The rectum stores poo before you pass it out of your body. Most people will have problems with their bowel function for several weeks after rectal cancer surgery. And for many, these problems can continue for around a year. Although it is unlikely that your bowel habits will return to how they were before surgery, these problems should become less severe with time.

But some people can develop a long term condition called low anterior resection syndrome, or LARS. This syndrome is a group of bowel problems after surgery for rectal cancer. These problems can include:

• opening your bowels more often (frequency)

• getting a strong urge to open your bowel and constantly feeling like you need to poo (urgency)

Chemotherapy

​Diarrhoea​ is a side effect of some chemotherapy drugs. Chemotherapy can inflame and irritate the lining of the bowel. This side effect of chemotherapy should settle down quite quickly.

Radiotherapy

Radiotherapy to the rectum can inflame the lining of the bowel. This can cause bleeding and looser, more frequent bowel movements. Side effects often get better within a few weeks of finishing treatment. But some people have these side effects months or even years later.

What can I do to help?

Your bowel habits might never return to how they were before your cancer treatment. But things should settle so that you develop a new ‘normal’ pattern. It might feel difficult at first. But remember that it’s likely to get better over time.

You can make some changes to help lessen the effects of treatment.

Diet

What you eat can make your poo looser or give you more wind. You might need to experiment a bit to find out which foods upset you. Everyone is different and there are no set rules about what you should eat. But the foods most likely to cause problems are:

• very high fibre fruits and vegetables

• onions, brussels sprouts and cabbage

• pulses such as baked beans or lentils

• fizzy drinks, beer and lager

• very rich or fatty foods

You can slowly increase different foods in your diet and see how your bowels cope. If you find a food upsets your bowels, you can cut it out and try it again after a few weeks. Ask to see a dietitian if you have problems. They can give you tips and help you to work out which foods upset you.

Read more about eating after bowel cancer treatment

Medicines

Your doctor or nurse might recommend that you take medicines to help your bowels. Talk to your doctor before you take any of these medicines.

Loperamide (Imodium) can help if you have frequent, watery poo. It works by slowing down your bowel so it takes longer for poo to pass through. This gives the bowel more time to absorb water so the poo is less runny. It can also reduce how often you need to go.

Your doctor might also suggest fybogel. This helps to bulk out loose poo and can help if you are pooing small amounts frequently.

For constipation, your doctor might give you stool softeners or laxatives.   

Skin care

Pooing more often can make the skin around your back passage sore. You should try to keep it as clean and dry as possible. Your doctor might recommend creams such as E45 or sudocrem.  

Other tips include:

• after pooing, wipe gently with soft toilet paper

• wash the skin with tepid water and simple soaps – don’t use perfumed or medicated soaps or other products. Use just warm water for skin that may be broken

• pat dry the skin with a soft towel – or you can use a hairdryer on a cool setting

• wearing loose, comfortable underwear and clothing can help

Talk to your healthcare team if you have soreness that isn’t improving. Sometimes a barrier cream can help.

Toileting habits and bowel function after treatment

Your nurse specialist or doctor might talk to you about your toileting habits. These habits include how long you spend on the toilet and at what point you go to the toilet when you feel the urge.

Try not to sit and strain on the toilet for long periods – speak to your nurse or doctor if you find you’re doing this. And try to hold on until the urge to poo is strong. This might be difficult at first. But over time you will become more familiar with how long you can hold on before you need the toilet.

Give yourself plenty of time and try not to feel rushed. It can take time and perseverance to re-train the bowel after treatment.

Reproduced and distributed with the kind permission of the co-authors, including Wendy Ness, Colorectal Nurse Specialist. Produced as a service to the medical profession by Norgine Ltd. ©2017 Norgine group of companies

Exercises

Exercises can help you strengthen the muscles you use to control your bowels. This can help prevent leaking.

You use 2 groups of muscles to control your bowels - the sphincter muscles in your back passage and your pelvic floor muscles. Your doctor or nurse can tell you whether pelvic floor exercises might help you, and they can teach you how to do them.

Go to the Bladder and Bowel Community website for more information on pelvic floor exercises