Diarrhoea and cancer treatments

Diarrhoea can be caused by chemotherapy|, radiotherapy|, biological therapies| and surgery. The treatments can affect the healthy cells that line the digestive tract, which causes diarrhoea. Sometimes medications or an infection can also cause diarrhoea.

This can be a temporary, mild side effect but for some people it can be severe and they will need to see a doctor to help manage it.

• Tell your doctor if you have diarrhoea. They can investigate the cause, and prescribe some anti-diarrhoea medicines.
• Make sure you drink plenty of fluids to replace the water lost with the diarrhoea, but avoid alcohol and coffee. 
• Acidophilus or other bacteria found in live yoghurt or live yoghurt drinks may help to ease diarrhoea caused by antibiotics. Antibiotics can kill off the healthy bacteria normally found in the bowel, but the bacteria found in live yoghurt may replace them. However, you should avoid live yoghurt while you’re having chemotherapy or if your immunity is low.
• Eat small, frequent meals made from light foods such as dairy produce, white fish, poultry, well-cooked eggs, white bread, pasta or rice. Avoid highly spiced or fatty foods and eat your meals slowly.
• Avoid foods and drinks that make the diarrhoea worse. This includes greasy, fatty foods such as chips and beefburgers, cooked dried beans, apple juice, raw fruits and vegetables, and spicy foods like chilli peppers.

If your diarrhoea is caused by radiotherapy or chemotherapy, changing your diet is unlikely to help. It’s important that you take the anti-diarrhoea medicines prescribed by your doctor. If you have diarrhoea after surgery for bowel cancer, discuss it with your doctor or specialist nurse before changing your diet.