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Constipation

Symptoms of constipation

If you are constipated, you won’t have regular bowel movements (poo, stools or faeces). You might not have one for a few days or more.

Early symptoms of constipation

The early symptoms of constipation can include:

  • difficulty and pain when passing a poo

  • fewer than 3 poo's a week

  • having to strain a lot when trying to open your bowels

  • hard, dry or lumpy poo that can look like small hard pellets or be unusually large

  • feeling that you have not completely emptied your bowel

  • feeling bloated and sluggish

Severe constipation

Severe constipation can cause more serious symptoms such as:

  • a swollen, hard tummy (with or without pain)

  • very liquid diarrhoea that you can’t control at all (overflow diarrhoea)

  • loss of appetite

  • feeling and being sick

  • headaches

  • confusion and feeling restless

  • being unable to pass urine (urinary retention)

What to do if you have constipation

Make sure that you get early treatment for constipation. It will make it much easier to sort the problem out. Leaving constipation for too long can lead to more serious problems such as a bowel blockage (obstruction).

Find out about the causes of constipation

Last reviewed: 17 Sept 2025

Next review due: 17 Sept 2028

Causes of constipation

You might be constipated when you have cancer. There are several possible causes such as the cancer or it's treatment.

Assessing your constipation

Before you have treatment for constipation, your doctor or nurse will need to find out how bad it is and what the cause could be. Find out what they might do.

Faecal impaction

Faecal impaction means having dry, hard poo (stool or faeces) in the back passage (rectum). Long term or chronic constipation can lead to faecal impaction.

Diet, fluid and physical activity

You might be able to manage constipation through diet, drinking plenty and being physically active. Find out more about how these can help.

Medicines for constipation (laxatives)

Laxatives can help you empty your bowels if you're constipated. If you have cancer speak to your healthcare team before taking any type of laxative.

Constipation main page

Constipation means having difficulty opening your bowels. Find out the causes, symptoms, and treatment of constipation.

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