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Brain and spinal tumours

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Potential side effects of biological therapy for brain and spinal cord cancer

Side effects can occur with any type of treatment for brain and spinal cord cancer, but not everyone has them or experiences them in the same way. Side effects of biological therapy will depend mainly on:

  • the dose
  • the person’s overall health

Side effects can happen any time during, immediately after, or a few days or weeks after biological therapy. Most side effects go away after biological therapy is finished. Late side effects can occur months or years after biological therapy. Some side effects may last a long time or be permanent.

It is important to report side effects to the healthcare team. Doctors may also grade (measure) how severe certain side effects are. Sometimes biological therapy needs to be adjusted if side effects are severe.

Flu-like symptoms

Flu-like symptoms are a common side effect of several biological therapies. Symptoms include:

  • fever
  • chills
  • muscle and joint aches or pain
  • headache
  • nausea
  • vomiting

These symptoms often occur immediately following treatment but lessen with time. Giving the injection before bedtime and taking other medications, such as acetaminophen (Tylenol), can help reduce these side effects and allow some people to sleep through them. Flu-like symptoms usually go away with continued therapy, once the body gets used to the drug. Check with the doctor or healthcare team if these symptoms do not go away or are bothersome.

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Fatigue is a common, temporary problem that can occur with certain biological therapy drugs. It is often related to the dose of biological therapy drug given and often goes along with flu-like symptoms.

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Diarrhea is an increase in the number and looseness of stools. It occurs because biological therapy may affect the cells that line the gastrointestinal tract. Many factors increase the risk of diarrhea, including the dose of biological therapy drug.

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Constipation is when stools become hard, dry and difficult to pass. Many factors increase the risk of constipation, including the medications given with biological therapy to relieve symptoms, such as muscle and joint pain, and decreased fluid intake.

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Sore mouth

A sore mouth (also called stomatitis or oral mucositis) occurs because of biological therapy’s effect on cells inside the mouth. Many drugs can cause a sore mouth and it occurs more often when higher doses of drugs are used. A sore mouth occurs about a week (anywhere from 5–14 days) after biological therapy starts. It often improves on its own a few weeks after treatment is finished.

Painful mouth sores, ulcers in the mouth and mouth infections can also develop. Thorough, regular mouth care can help prevent a sore mouth and reduce infection. The healthcare team will give instructions about how often to clean and rinse the mouth and what to use. Pain medicines or special oral solutions may be needed to relieve pain.

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Change in blood pressure

The biological therapy drug bevacizumab can raise (more common) or lower a person’s blood pressure. This is not a common side effect. Blood pressure is monitored, especially when drug therapy is first started. Getting up slowly may help prevent dizziness. Dizziness that occurs when a person is standing should be reported to the doctor.

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Skin infection

The drug bevacizumab (Avastin) can cause severe skin infection. Symptoms include fever, swelling that is red, hot and very painful, fluid-filled blisters in the skin or discoloured skin over the affected area. This infection can spread quickly and destroy layers of tissue around the muscle.

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Note: Other side effects may occur. For more detailed information on specific drugs, go to sources of drug information.


Dave McKeage Within about 12 hours of being at Camp Goodtime, everything started to change, and that week was cathartic, transformative. It was the first time I got to know myself.

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