If you’ve been diagnosed with cancer and you’ve had trouble concentrating on a task, remembering words or directions, doing several things at once, or recalling a date or phone number, you may be experiencing cognitive changes after cancer treatment, often called “chemobrain.”

Chemobrain describes thinking or cognitive problems, such as issues with short-term memory or word-finding. It may start after a cancer diagnosis or after cancer treatment. It’s normal to feel frustrated or worried about these symptoms.


You are not alone

Even though you may have never heard of it, chemobrain is real. Up to 75 percent of people with breast cancer who have chemotherapy report symptoms of chemobrain during active treatment.

Despite its name, chemobrain symptoms may not only be due to chemotherapy. They can be caused by other medicines used for breast cancer treatment (including hormonal therapies) or other experiences related to going through cancer treatment. People treated for other types of cancer may also develop chemobrain.

Chemobrain is seen in people of all ages. Older women may be at more risk, but young women also have difficulty with symptoms.


What causes chemobrain?

The reasons for chemobrain are under study, but there are several potential contributing factors:

  • Chemotherapy, radiation therapy, and other cancer treatments may set off chemical reactions (such as inflammation) that can affect your cognition, similar to how you may feel when you have the flu.
  • Some chemotherapy medicines may cross the blood-brain barrier. That means some chemotherapy may pass into the brain and affect its functioning.
  • People taking hormonal therapies, such as tamoxifen and aromatase inhibitors, may also report some chemobrain symptoms. This is due to lowered estrogen levels, which can have an impact on brain function.

Besides cancer treatment itself, other factors related to the entire cancer experience may contribute to some chemobrain symptoms. These may include:


How long does chemobrain last?

Everyone’s chemobrain experience is different. Most people stop having these symptoms 6 to 9 months after completing cancer treatment. Still, about 25 percent of women continue to struggle with chemobrain. Some may have symptoms that last for years.


How can I manage chemobrain?

There are many practical ways you can address chemobrain. Talk with your doctor and healthcare team. It may help to keep a record of symptoms and when they occur. Bring the information to your next appointment with your care team and let them know what you’re experiencing. They might suggest a change in medicine to avoid side effects, or another approach.

These tips may also help you function better:

  • Get enough sleep. Try to get 8 to 9 hours of sleep at night.
  • Increase your activity. Aim for moderate exercise, such as walking, yoga, or tai chi, at least three times a week. Even a short walk around the block with a friend or a pet can help. Exercise seems to help many people with cognitive issues.
  • If you’re feeling stressed, try some stress management strategies. Use music or a calming activity, such as knitting or reading. Consider meditation and other stress-reducing techniques. Cognitive problems are often magnified when we are under severe stress.
  • If you feel depressed or anxious, talk with your doctor. Treating depression often helps with cognition. A referral to an oncology social worker or mental health professional may help.
  • Improve your nutrition. Consider decreasing processed and sugary foods in favor of whole foods that have fruits, vegetables, and healthy fats and protein. A nutritionist may help you improve your diet based on your needs.
  • Use lists, calendars, and planners to help you focus and remember important details.
  • Organize your living and work spaces. Choose specific places to store items, such as keys or remotes, and always return them to the same spots.
  • Socialize. Feelings of chronic loneliness and isolation may put some at greater risk for cognitive problems. Interact with others in ways you enjoy.

Here are some specific tips to help you improve your focus:

  • Try to do one thing at a time. We often multitask, but sometimes it helps to focus on the issue at hand.
  • Follow a routine. Having a pattern can help you focus.
  • Choose quiet places with limited distractions to read, study, or have an important conversation.

If chemobrain feels very intrusive and your doctor doesn’t offer much help, ask to be referred to a speech therapist or a neuropsychologist, a doctor with special training in the connections between the brain and behavior.

In some situations, your doctor may recommend certain medicines, such as methylphenidate (Ritalin) or modafinil (Provigil), to help improve your concentration.


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Reviewed and updated: August 26, 2022

Reviewed by: Arash Asher, MD


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