Symptom Management, Palliative Care, or Supportive Care to relieve side-effects is an important part of cancer care and treatment and should always form part of the overall treatment plan.

Diarrhoea is frequent, loose, or watery bowel movements, and something that virtually every one of us has experienced or will experience at some or other time. Diarrhoea can be a symptom of infection, food poisoning, colitis, a gastrointestinal tumour, or as a result of cancer treatment.


Diarrhoea may be caused by chemotherapy, radiation therapy to the pelvis, the cancer itself, or by conditions unrelated to the cancer. The causes and treatments of your child’s diarrhoea could be varied, and it is important that you speak to their oncologist as soon as possible.

Other reasons that a person with cancer might have Diarrhoea include:

Antibiotics: An individual may develop a diarrhoea-causing infection with bacteria called Clostridium Difficile from exposure to antibiotics

Bowel: An individual who has had any part of his or her bowel removed may have diarrhoea related to the shorter area of bowel that can reabsorb water from foods

Pancreas: Inability of the pancreas to absorb fatty foods may happen if an individual’s pancreas is affected by cancer; it can lead to greasy stools with a distinctive bad odour

GVHD: Individuals who have received a bone-marrow transplant may get Graft-Versus-Host-Disease which can cause diarrhoea

General: Any individual, including those with cancer, can develop diarrhoea from conditions such as irritable or inflammatory bowel disease or viral infections.


Diarrhoea may be described according to the following stages, from mild to severe, as established by the National Cancer Institute (NCI):

  • Stage 1 is an increase of less than four stools a day.
  • Stage 2 is an increase of four to six stools a day.
  • Stage 3 is an increase of more than seven stools a day, incontinence, or a reduced ability to care for your own daily needs; hospitalization is recommended.
  • Stage 4 is a life-threatening condition that requires immediate intensive care.

Treatment & Prevention

Preventing Diarrhoea or treating it early can help your child avoid dehydration or other problems. It is best to discuss your child’s symptoms with their health care team, as the correct solution to the problem depends greatly on the cause.

The following may help you manage your child’s mild diarrhoea (stage 1 or 2):

  • Do not give your child caffeine, dairy, fat, fibre, orange juice, prune juice, or spicy foods
  • Do not give your child laxatives or stool softeners
  • Give your child small, frequent meals, and ask their doctor which foods are best for them to eat when they have diarrhoea. Foods that are easy for the stomach to digest include bananas, rice, applesauce, and toast. Additional dietary changes may be recommended by your child’s health care team.
  • Give your child plenty of water and other clear liquids to prevent dehydration. People with severe dehydration may need to receive intravenous (IV, through a vein) fluids.
  • Ask your doctor about changing the schedule or dose of chemotherapy if the Diarrhoea is caused by the treatment and is severe.

Speak to your child’s oncology team about giving them anti-diarrhoeal medications – Imodium is often used to treat Diarrhoea caused by some types of chemotherapy.