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What is Chemo Brain?

  • Updated: January 28, 2021

    Chemo brain is the mental cloudiness or "brain fog" that many cancer patients experience after chemotherapy. This mental fog may mean you forget things you used to automatically remember.

    You may have trouble focusing, particularly if you are trying to multitask or think through something complex. You may just feel a little slower or a little confused.

    It is not imaginary—it is a real phenomenon, according to Margaret von Mehren, MD, Chief of the Division of Sarcoma Medical Oncology at Fox Chase Cancer Center. “My patients who have experienced it typically report a decline in mental acuity and ability to remember. It can be a mild annoyance that disappears after therapy is done, or a greater concern if it affects daily activities,” von Mehren said.

    How long does chemo brain last?

    Cognitive problems can start during or after treatment and, for some patients, even earlier due to cancer symptoms and the stress of the diagnosis itself. Chemo brain can be subtle, come on quickly, and fade within weeks, or it may be more pronounced or longer lasting.

    Common chemo brain symptoms

    Some typical signs include:

    • Trouble remembering details, words, names, or dates
    • Misplacing things
    • Inability to concentrate, short attention span
    • Feeling slow, disorganized, or confused
    • Inability to multitask

    What causes chemo brain?

    It is not clear if certain chemotherapy drugs are more likely than others to cause chemo brain, or why certain patients report symptoms and others don’t, von Mehren noted.

    It is good to recognize that things other than chemotherapy can cause a foggy brain. Some can be addressed fairly easily, like dehydration, nutritional deficiencies, or lack of exercise. Others can be complications of cancer, like anemia or menopause. Chronic stress, insomnia, anxiety, depression, and pain affect mental acuity. Paradoxically, medications for pain, sleep, anxiety, depression, anemia, nausea, and drugs to combat infection can also cause cognitive clouding.

    “Pain can be physically and emotionally draining, adding to the chemo brain. Sometimes the medications used to address pain may be sedating or may impact a clear thought process,” von Mehren said. With so many causes, it is easy to see why some people have difficulties thinking and remembering during and after chemotherapy treatment.

    Can chemo brain be treated?

    Unfortunately, there is no cure or medication for chemo brain, but there are several helpful suggestions that are likely to serve you well throughout your survivorship:

    • Establish regular routines, like putting your keys in the same place every day
    • Leave yourself reminders, but you don’t have to remember everything yourself—consider relying on family members, your care team, and computer searches to be part of your extended memory
    • Keep a calendar
    • Try to do one thing at a time; multi-tasking is the enemy of productivity
    • Prioritize getting enough sleep
    • Add some physical activity to your day if possible—walking, gardening, swimming, and yoga are all possibilities
    • Try a new activity—it is not necessary to be good at piano or Sudoku—just giving something new a try exercises the brain
    • Tell your care team if you have symptoms or feel anxious or depressed—keeping a journal of your signs and symptoms can help you and your doctor measure how your life is being affected

    Most of all, be kind to yourself and remember that your care team and loved ones can provide the extra help you need.