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During Treatment

About This Resource  

Author: Waterloo Wellington Regional Cancer Program

Revised: March 2025

PEM#: PEMWRHNCC0009

Chemotherapy travels through your whole body.

It works to kill cancer cells, but can also affect healthy, fast-growing cells. This may lead to side effects in different areas of your body. The side effects below are listed in order of importance for people on chemotherapy.

Call your healthcare team if you have ANY side effects from the list below.

If you are feeling very unwell, go to an Emergency Department near you. Tell them you are a cancer patient on chemotherapy.

Side Effects & Symptoms

  • A fever of 38.3°C (101°F) or higher (even if this only happens once) OR 38.0°C (100.4°F) that lasts for more than 1 hour. Check your temperature at least 2 times a day (e.g. when you wake up and when you go to bed). You should check more often if you are feeling unwell.
  • New chest pain or sudden shortness of breath (having a hard time breathing) – go straight to an Emergency Department near you
  • Nausea or vomiting (throwing up) that continues for more than 24 hours or does not go away after taking your drugs for nausea
  • Diarrhea: more than 4 loose stools (poo) in 24 hours, mucous or blood in your stools (may look dark, sticky or tarry), severe stomach pains, tenderness, or cramping
  • Constipation (pooing less than normal) that lasts more than 72 hours
  • Sore throat or mouth (red or sore areas seen in the mouth)
  • Severe night sweats that need you to change your night clothes or bedsheets
  • Pain that is new, not going away, or getting worse
  • New or worsening weakness or numbness in your legs or arms
  • Unable to control when you pee or poo
  • Unusual swelling in your arm or leg
  • Having a hard time walking or staying balanced
  • Hearing or vision changes
  • Signs of serious bleeding: unusual bruising, heavy nosebleeds, blood in pee, blood in poo (may look dark, sticky or lumpy), blood in vomit (may look like dark coffee grounds), coughing up blood, or sudden intense headache
  • Changes in peeing: pain or burning while peeing, feel the need to pee often, unable to pee, or peeing in small amounts
  • Allergic reactions (during or within hours of getting the drug): sudden or severe rash; swollen lips, face or tongue; chest and throat tightness
  • Swollen, hot, tender, or red areas at your injection site, especially with a fever
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Use this resource for your information only. It does not replace medical advice from your doctor or other healthcare professionals.

Email: [email protected]

Website: www.cancerwaterloowellington.ca