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Mucositis From Cancer Treatment: Care Instructions

The parts of the digestive tract in the body, including mouth, throat, esophagus, stomach, small intestine, large intestine, and rectum


Mucositis is swelling and sores in the lining of your digestive tract. This includes your mouth, throat, esophagus, stomach, intestines, and rectum. When it's in the mouth, this problem is also called oral mucositis or stomatitis. Mucositis can cause mouth and throat sores that make it painful to eat, drink, or swallow. It may also cause chest and belly pain, nausea, diarrhea, and bloody stools.

Mucositis is a common side effect of cancer treatments such as some chemotherapy and radiation. It can make you more likely to get an infection in the digestive tract. Mucositis and its symptoms are treated with medicines and home care.

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse advice line (811 in most provinces and territories) if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.

How can you care for yourself at home?

  • Be safe with medicines. Read and follow all instructions on the label.
    • If the doctor gave you a prescription medicine for pain, take it as prescribed.
    • If you are not taking a prescription pain medicine, ask your doctor if you can take an over-the-counter medicine.
  • If you have pain or skin breakdown in your anal area from frequent diarrhea, you can sit in 8 to 10 centimetres (3 to 4 inches) of warm water (sitz bath) 3 times a day and after bowel movements. The warm water helps if you have pain and itching around your anus from sores or diarrhea.
  • If your doctor prescribed antibiotics or antifungals, take them as directed. Do not stop taking them just because you feel better. You need to take the full course of medicine.
  • Eat soft foods such as mashed potatoes and other cooked vegetables, noodles, applesauce, clear broth soups, yogurt, and cottage cheese. You can get extra protein by adding protein powder to milkshakes or breakfast drinks. Avoid eating spicy or crunchy foods.
  • Try eating cold foods such as ice cream or frozen yogurt.
  • Avoid drinking high-acid juices such as orange, grapefruit, and cranberry juice.
  • Drink plenty of fluids to prevent dehydration. If you have mouth sores, drinking through a straw may help with pain.

When should you call for help?

Call your doctor or nurse advice line now or seek immediate medical care if:

  • You can't drink fluids.
  • You have new or worse pain.
  • You have a fever.
  • You have diarrhea.
  • You have new or more blood in your stools.

Watch closely for changes in your health, and be sure to contact your doctor or nurse advice line if:

  • You have new or worse symptoms.
  • Your diarrhea does not get better, or it happens more often.

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