Not all treatments for prostate cancer will result in bowel problems. For some men, however, side effects of treatment involving the bowel can require further support and help. It is important to talk to your doctor and healthcare team about any bowel problems you are experiencing. They understand your individual situation and are able to give you the most relevant advice.


To understand how your bowel can be affected by prostate cancer, you first need to understand how your body works.

The prostate is a small gland below the bladder and in front of the rectum in men. It surrounds the urethra, the passage to the penis through which urine and semen pass. The location of the rectum (the lower part of the bowel) next to the prostate explains why some of the prostate cancer treatments can cause bowel symptoms in some men. This close location is shown in the following diagram:



After radiotherapy, bowel incontinence can affect quality of life for 1 in 5 patients.


Before your prostate cancer diagnosis, you might have experienced bowel problems for other reasons. These prior symptoms could return or be made worse by your treatment. After treatment, any new symptoms may or may not be related to your treatment and its effects on your bowel. Discuss this with your healthcare team.

It is important to let your doctor know as soon as possible if you experience bowel problems.

Bowel symptoms following prostate cancer treatment may include:

  • diarrhoea
  • constipation
  • leakage/soiling (bowel incontinence)
  • wind/gas
  • sudden and urgent need to open your bowels (urgency)
  • rectal bleeding.

These symptoms can vary from mild to more severe forms.


Bowel incontinence (also known as faecal incontinence) can be described as accidental leaking of faeces. The amount of leakage may vary from a drop to total loss of bowel control. After radiotherapy, bowel incontinence can affect quality of life for 1 in 5 patients.

The main issue with bowel incontinence is that it is rarely discussed or reported by men, so it is not highlighted as a major concern. Men can often overcome their distress by seeking advice and assistance from the healthcare team.


Bowel symptoms usually occur due to a weakening of the control muscles surrounding the rectum and inflammation in the bowel. These control muscles are called the internal and external sphincter.

There are many causes of bowel incontinence after treatment including:

  • faster digestion
  • bacterial growth in the bowel
  • treatment medications
  • fatty and high carbohydrate foods
  • psychological factors
  • muscle weakness.

The types of symptoms you experience can relate to the type of treatment you have.


Bowel symptoms are not an expected side effect of prostate cancer surgery. Report any bowel changes that occur after surgery to the healthcare team.

Constipation can be a problem immediately after surgery. To prevent constipation after the operation, it is important to:

  • follow any dietary instructions from your healthcare team
  • eat a healthy, well balanced diet including fruit, vegetables and high fibre foods
  • exercise regularly; but only after discussing with your healthcare team
  • drink plenty of water each day
  • use medications; you may be prescribed medications (laxatives, stool softeners) by your urologist to maintain regular soft bowel actions in the short term following your surgery.

Pushing or bearing down to expel a hard motion can affect the repair of the surgical site and the pelvic muscles that maintain continence. This is a key reason to attend to constipation without delay. The steps listed above can prevent damage after the operation.

If you develop any bowel symptoms after the surgery, discuss this with your treating doctor as soon as possible.


There are two main types of radiotherapy – external beam radiotherapy (EBRT) and brachytherapy. The difference is whether the treatment is applied from outside the body (EBRT) or delivered from within the prostate (brachytherapy).


External beam radiotherapy (EBRT) uses high energy X-ray beams that are directed at the prostate from the outside to destroy cancer cells.

Men treated with EBRT often have worse bowel function and are more bothered by it than men treated surgically.

Symptoms you may experience from EBRT are:

  • diarrhoea
  • gas and bloating
  • blood in your stool or passing of blood
  • urgency to have a bowel motion
  • increased bowel frequency
  • abdominal pain and discomfort when passing bowel motions
  • bowel incontinence.

Speak to a member of your healthcare team if you have any bleeding from the back passage and for suggestions that are specific to your needs.


Brachytherapy is when radioactive material is inserted directly into the prostate. It is given at either a high dose rate (HDR) or low dose rate (LDR).

You may have mild bowel problems in the first year after brachytherapy. Symptoms may even start two or three years after treatment. You may experience rectal bleeding or need to empty your bowels more often. If you are also having external beam radiotherapy, you are more likely to have bowel problems. Tell your doctor about any symptoms, as there are treatments available that can help.

  • High Dose Rate: is given by inserting radioactive material directly into the prostate. Unlike LDR seeds, the placement of the material is temporary and for shorter periods. As a result, the side effects for HDR can be similar to LDR seeds but usually shorter duration.
  • Low Dose Rate: is given by implanting permanent radioactive seeds directly into the prostate. The seeds give off concentrated amounts of radiation to the prostate with the aim of killing the cancer cells.

Side effects usually start to occur anywhere from 1 – 6 weeks after LDR brachytherapy. Some patients may experience ongoing problems, but serious long term side effects are uncommon. Some of these may include persistent rectal bleeding and diarrhoea.

Discuss your feelings with someone close, this may help you cope and make sense of your situation.


Chemotherapy uses drugs to destroy cancer cells in advanced prostate cancer when the cancer has spread to other parts of the body. The medication reaches cells through the bloodstream and may also affect healthy cells in your body.

Some chemotherapy drugs can cause constipation or diarrhoea. If you experience any of these symptoms for longer than a couple of days, let your treating doctor know. Prolonged episodes of diarrhoea can cause dehydration and will need to be treated.


HIFU is an emerging therapy which uses intense heat applied through the rectum to destroy the prostate and the contained prostate cancer. It is useful in older patients who are unsuitable for surgery or radiotherapy.

HIFU can cause a burning sensation or some bleeding from the rectum. This is most common in patients treated with multiple HIFU sessions.

Very rarely, HIFU causes a hole (fistula) between the urethra and the rectum. This affects less than 1 in 100 men (1 per cent). It is more common for men who have already had radiotherapy. Recent studies suggest that about 3 in 100 men (3 per cent) who have HIFU after external beam radiotherapy develop a fistula.

Sometimes pain and infections of the urethra can be early signs of a fistula, although there may be other causes. Contact your doctor or nurse if your urine is strong smelling or you have a temperature after the treatment, as these could be signs of an infection. Discharge from the urethra or discharge or diarrhoea from the rectum after HIFU may also be signs of a fistula. If you develop a fistula, you may need to have an operation to repair the hole.

Bowel symptoms are not an expected side effect of prostate cancer surgery. Report any bowel changes that occur after surgery to the healthcare team.