Cancer RehabilitationChemotherapySide-Effects Management

Dealing with Chemo Brain

Cognitive changes during cancer treatment, also known as “chemo brain” or “chemo fog,” are common. In fact, some studies suggest that up to 75% of patients receiving chemotherapy may face these issues.
October 2015 Vol 1 No 5
Arash Asher, MD

I am in the middle of chemotherapy, and I think I might have “chemo brain.” I feel tired, forgetful, and a bit discouraged. What is chemo brain? What is the difference between chemo brain and cancer-related fatigue? If I do have chemo brain, what can I do about it?

Cognitive changes during cancer treatment, also known as “chemo brain” or “chemo fog,” are common. In fact, some studies suggest that up to 75% of patients receiving chemotherapy may face these issues. “Chemo brain” may not be the best term to describe this problem, because many causes other than chemotherapy contribute to these common cognitive problems.


Chemo brain symptoms vary from person to person, but the typical symptoms include:

  • Forgetfulness
  • Word-finding difficulties (“I have a word on the tip of my tongue and I just can’t find it”)
  • Difficulty with multitasking
  • Impaired concentration or attention
  • Short-term memory challenges (Note that old memories, problem-solving, and reasoning skills are not issues that patients typically experience with chemo brain.)


It is often difficult to differentiate between the symptoms of chemo brain from cancer-related fatigue and those from depression. Cancer-related fatigue affects many patients who receive cancer treatment and can involve mental and physical fatigue. The key is that unlike typical fatigue that resolves with a nap or good night’s sleep, the fatigue related to cancer and its treatment persists.

Cancer-related fatigue may worsen the symptom of chemo brain or vice versa. For example, if you are exhausted after doing some chores, it may be hard to think clearly. Or, if you are spending more energy than normal doing a cognitive task, such as balancing your checkbook, it may lead to fatigue; it is often hard to know which came first. For this reason, many researchers believe that cancer-related fatigue and chemo brain are manifestations of the same process.

Depression also shares many symptoms with cancer-related fatigue and chemo brain. Depression may lead to forgetfulness, poor concentration, fatigue, and poor sleep. So, working with your doctor to try to differentiate between the symptoms of cancer-related fatigue, chemo brain, and depression is very important for tailoring your treatment.


  • Chemotherapy, radiation therapy, and other cancer treatments may set off chemical reactions that can affect your cognition, similar to how you may feel when you have the flu
  • Some chemotherapy drugs may pass into the brain and affect its functioning
  • Hormonal therapies that may be used for prostate or breast cancer can result in chemo brain symptoms

Many other health-related issues may contribute to cognitive problems, such as:

  • Poor sleep
  • Chronic stress
  • Taking other medications, including pain, nausea, or sleep medications
  • Poor nutrition
  • Lack of exercise or physical activity


Patients can experience chemo brain for a different duration. The good news is that the majority (approximately 75%) of cancer survivors return to their baseline cognition within 6 to 12 months after completing their treatment. However, about 33% of survivors continue to struggle with these symptoms for months or sometimes for years after treatment.


Get enough sleep. The impact of inadequate sleep on cognition can’t be overstated.

Moderate exercise. Research shows the positive impact of aerobic exercise on our cognition, including research on patients with chemo brain; walking, swimming, yoga, or cycling are all helpful.

Talk to your doctor. Many of the symptoms of depression are confused with chemo brain. Treating depression, if you have it, often helps with cognition.

Optimize your nutrition. The brain seems to work best with a whole diet with fruits, vegetables, healthy fats, and protein as opposed to excessive sugar and processed foods. A nutritionist may help you develop a program that meets your needs.

Seek help from a neuropsychologist or a speech pathologist. These experts can provide you with coping strategies and new cognitive skills.

Mindfulness meditation, yoga, and other stress management techniques can help reduce anxiety and depression, which worsen the symptoms of chemo brain.

Organize your living and work spaces. Choose specific places to store items, such as keys or glasses, and return them to the same spots.

Do just one thing at a time rather than multitasking

“Brain games,” such as Sudoku, crossword puzzles, or computer training programs won’t hurt, but probably won’t address the complex, real-world cognitive challenges you may face with chemo brain. Brain games are under study, so be cautious before purchasing any expensive brain-game program.

No medications have proved to work for chemo brain so far. Nevertheless, when these strategies are inadequate, it may be worth it to consider “stimulant” medications, such as Ritalin (methylphenidate) or Provigil (modafinil), in some situations.

Share this:

Recommended For You
Side-Effects ManagementFinancial Support
Drugs for Side-Effects Management (Supportive Care)
Find financial assistance programs available for side-effect drugs.
Side-Effects Management
Managing versus Preventing Side Effects: What Is the Difference?
By Lillie D. Shockney, RN, BS, MAS, HON-ONN-CG
Our own Lillie Shockney dives into the differences between managing and preventing treatment side effects, including the benefit of walking before radiation and how to deal with hair loss.
Side-Effects ManagementBreast Cancer
Dealing with Chest Numbness After Mastectomy
By Kristen Casey, PsyD
Chest numbness is a side effect often ignored or not discussed in breast cancer, but losing physical sensation in nearly 10% of the body can have a profound impact on a woman’s physical and emotional life.
Oral HealthSide-Effects Management
Simple Strategies for Relieving Oral Pain Caused by Cancer Treatment
By Kris Potts, BS, FAADH, RDH
Dental hygienist Kris Potts breaks down the side effects, such as dry mouth and oral ulcers associated with cancer treatments and lists treatments available to combat these problems.
Last modified: March 10, 2022

Subscribe to CONQUER: the patient voice

Receive timely cancer news & updates, patient stories, and more.

Race or Ethnicity
Profession or Role
Primary Interest
Other Interests