Overview

Chemo brain is a common term used by cancer survivors to describe thinking and memory problems that can occur during and after cancer treatment. Chemo brain can also be called chemo fog, cancer-related cognitive impairment or cognitive dysfunction.

Though chemo brain is a widely used term, the causes of concentration and memory problems aren't well-understood. It's likely that there are multiple causes.

No matter the cause, chemo brain can be a frustrating and debilitating side effect of cancer and its treatment. Researchers are working to understand the memory changes that people with cancer experience.

Symptoms

Signs and symptoms of chemo brain may include the following:

Being unusually disorganized

Confusion

Difficulty concentrating

Difficulty finding the right word

Difficulty learning new skills

Difficulty multitasking

Feeling of mental fogginess

Short attention span

Short-term memory problems

Taking longer than usual to complete routine tasks

Trouble with verbal memory, such as remembering a conversation

Trouble with visual memory, such as recalling an image or list of words

When to see a doctor

If you experience troubling memory or thinking problems, make an appointment with your doctor. Keep a journal of your signs and symptoms so that your doctor can better understand how your memory problems are affecting your everyday life.

Causes

There are many possible factors that might contribute to the signs and symptoms of memory problems in cancer survivors.

Cancer-related causes could include:

Cancer

A cancer diagnosis can be quite stressful and it might lead to anxiety and depression, which can contribute to thinking and memory problems

Certain cancers can produce chemicals that affect memory

Cancers that begin in the brain or spread to the brain might cause changes in thinking

Cancer treatments

Bone marrow transplant

Chemotherapy

Hormone therapy

Immunotherapy

Radiation therapy

Surgery

Targeted drug therapy

Complications of cancer treatment

Anemia

Fatigue

Infection

Menopause or other hormonal changes (caused by cancer treatment)

Sleep problems

Pain due to cancer treatments

Other causes

Inherited susceptibility to chemo brain

Medications for other cancer-related signs and symptoms, such as pain medications

Other medical conditions, such as diabetes, thyroid problems, depression, anxiety and nutritional deficiency

Risk factors

Factors that may increase the risk of memory problems in cancer survivors include:

Brain cancer

Cancer that spreads (metastasizes) to the brain

Higher doses of chemotherapy or radiation

Radiation therapy to the brain

Younger age at time of cancer diagnosis and treatment

Increasing age

Complications

The severity and duration of the symptoms sometimes described as chemo brain differ from person to person. Most cancer survivors will return to work, but some will find tasks take extra concentration or time. Others may be unable to return to work.

If you experience severe memory or concentration problems that make it difficult to do your job, tell your doctor. You may be referred to an occupational therapist or a neuropsychologist, who can help you adjust to your current job or identify your strengths so that you may find a new job.

In rare cases, people with memory and concentration problems are unable to work and may consider applying for disability benefits. Ask your health care team for a referral to an oncology social worker or a similar professional who can help you understand your options.