During chemotherapy treatment, you may experience different side effects. These can vary depending on the type of cancer you have and the stage of your cancer. However, a common side effect that you may have heard of is chemo brain.

Chemo brain or chemo fog is a term used to describe thinking and memory problems which may occur during or after chemotherapy treatment.

The medical term for chemo brain is cancer-related-cognitive-impairment (CRCI).

The exact cause of chemo brain is not fully known. However, research suggests that it is not just the direct effect of the chemotherapy medication itself causing chemo brain.

Other possible causes are:

• The cancer itself
• Chronic stress affecting the part of the brain responsible for learning and memory
• Genetic factors

It is thought that other factors such as anxiety, depression and sleep problems may also contribute to chemo brain.

Chemo brain may impact you in different ways, and can affect:

• the working memory, for example forgetting names and having difficulty following directions
• verbal memory, for example feeling that they are unable to keep up with a conversation
• processing speed, for example having difficulty learning new skills and problem solving

Cancer patients who experience chemo brain may have trouble remembering, learning new things, concentrating, or making decisions affecting everyday life, such as:

• having difficulty concentrating
• being forgetful
• having problems making decisions
• having problems multi-tasking
• taking longer to finish things
• having trouble remembering common words
• having problems learning new things

While it is not fully known how common ‘chemo brain’ is, it has been estimated that it can affect up to 75% of cancer patients in some form.

Up to 35% of cancer survivors can experience difficulties for months, even years, following treatment.

A number of medications and herbs have been studied as possible treatments for chemo brain but so far there has been no proven benefit from any medication.

Other strategies that have been shown to have some benefit in helping to improve symptoms include:

• Brain training – Brain games or exercises, either face-to-face or online
• Memory training – Memory aides such as checklists and keeping to a daily routine to decrease decision making requirements
• Exercise – Exercise, such as yoga and tai chi can improve your attention and concentration levels
• Mind and body – Mindfulness, meditation, acupuncture

While chemo brain is a common problem, remember that it is likely to improve with time.

Stress and tiredness can contribute to memory and concentration problems, so try to get plenty of rest and do regular relaxation techniques and activities (including exercise).

Be open with your friends and loved ones about your chemo brain symptoms and let them know how they can support you during this time.

Specialised health services known as allied health can help you and your family cope with treatment side effects. You can find out about the different allied health specialists, such as psychologists and occupational therapists, and how they can help here.