Written by Dr. Savannah Muncy, Pharm.D on
December 29, 2021
Reading Time: 6 minutes

Medically Reviewed by our Medical Affairs Team

Written by Dr. Savannah Muncy, Pharm.D on:

Are you undergoing chemotherapy, and you feel like your brain is not working? Do you struggle to remember things? If so, chemo brain fog might be the culprit.

Chemotherapy can damage cells in the parts of the brain that control memory. It’s a common side effect, and it can happen with any type of chemo treatment for cancer or other diseases.

In this blog post, we’ll explore the chemo brain, the causes and symptoms of brain fog, and how to manage it so that you don’t get frustrated trying to do all the things on your list.

So, let’s get started.

What is a chemo brain?

The chemo brain is a term used to describe the cognitive effects of chemotherapy. It’s also called chemo fog, cancer fog, and chemo-induced cognitive impairment (CICI).

Chemotherapy can damage cells in the parts of the brain that control memory, concentration, problem-solving, and multitasking. The chemo brain is one of chemo’s most common side effects, and chemo brain symptoms can vary.

It may feel like you’re struggling to remember things or find the right words when speaking. You might take longer than usual to do simple tasks that used to be second nature. And chemo brain symptoms often get in the way of everyday activities.

Chemo brain can start during chemo and last for months, years, or even be permanent. The chemo brain symptoms you experience will depend on the type of chemo treatment (the drugs used), their dose and schedule, your overall health when you’re treated, and other factors like genetics that are still being researched.

Causes of Chemo Brain Fog

Chemo drugs may cause chemo brain, but they can also start when chemotherapy is finished.

The chemo drugs that are most likely to cause chemo brain include:

Some chemo drugs cause other chemo brain symptoms. For example, chemo drugs that affect the nervous system (like vincristine and carboplatin) can cause chemo brain as well as chemo-brain nerve pain.

Sometimes, chemo drugs are used to treat conditions other than cancer. For example, chemotherapies for autoimmune disorders may lead to chemo brain since they attack both healthy cells and diseased cells.

The chemo brain symptoms you experience will depend on the type of chemo treatment (the drugs used), their dose and schedule, your overall health when you’re treated, and other factors like genetics that are still being researched.

Symptoms

Chemo brain symptoms may appear when chemo drugs are in your body or after they’re gone.

In either case, the chemo brain usually gets worse over time and makes it more difficult to remember things.

It can also make you feel frustrated since the chemo brain can interfere with everything from simple tasks like cooking dinner to complex tasks like keeping track of your car keys.

Chemo brain symptoms can include:

  • Difficulty concentrating or thinking clearly
  • Feeling forgetful, not remembering important things or events, and struggling to recall memories you’d usually remember easily.
  • Slower mental responses (like taking longer to answer a question)
  • Trouble multitasking
  • Feeling tired and run-down, especially during chemo but also for weeks or months after chemo ends.
  • Having trouble sleeping
  • Changes in mood, such as feeling irritable, anxious, or depressed
  • Experiencing chemo-brain nerve pain (which is different from regular chemo brain fog pain).

Complications

Chemo brain can cause complications if it interferes with your ability to do everyday activities.

Complications of chemo brain may include:

  • Difficulties carrying out tasks at work or home that you usually handle without a problem, such as keeping track of the family schedule and paying bills on time
  • Increased risk for accidents
  • Lower quality of life and emotional distress

Some chemo brain complications can be dangerous. For example, the chemo brain may lead to an increased risk for accidents since it makes driving or working with machinery more difficult.

In some cases, chemo brain can cause physical problems as well if you don’t take steps to manage your symptoms. For example, chemo brain fog can lead to dehydration if you’re not drinking enough fluids.

Also, since chemo drugs that affect the nervous system (like vincristine) can also affect your body’s healthy cells, you may experience some chemo side effects even if you don’t have cancer.

Doctors and researchers are still trying to understand all of the ways chemo drugs can affect both diseased cells and healthy cells.

The chemo brain symptoms you experience will depend on the chemo drugs you’re on and how much brain fog is caused by chemotherapy itself versus other factors.

Some people find that their chemo brain clears up after treatment ends, while others have persistent chemo side effects like memory problems or physical issues.

It’s important to talk with your oncologist about any problems you’re having with the chemo brain and come up with a plan to manage them.

Diagnosis

There’s no one test to diagnose chemo brain fog.

Your doctor may ask you a range of questions about how the chemo drugs are affecting your thinking, mood, and daily activities.

They will also want to know if you have any chemo side effects that aren’t related to cancer (like chemo brain fog pain).

In some cases, chemo brain can be diagnosed based on your symptoms and how chemo affects you.

However, there’s no specific test to diagnose chemo brain fog at this time.

Management and Treatment

Since chemo brain fog can be frustrating and make it difficult to do everyday activities, you’ll likely want to take some steps to manage it.

Some ways to manage chemo brain fog include:

  • Making a list of things you need to remember and carry it with you
  • Using a planner or calendar to keep track of appointments and other important dates
  • Breaking down complex tasks into smaller, more manageable steps
  • Asking for help when you need it
  • Keeping a positive attitude–chemo brain fog can be frustrating, but it doesn’t mean that you’re losing your mind or that the chemo isn’t working.

No one chemo brain fog treatment works for everyone. Some people find that strategies like those listed above help, while others need medication to manage their chemo brain symptoms.

Your oncologist can work with you to come up with a plan that helps you manage chemo brain fog and still live a full and productive life.

Memory Aids

There are a few things you can do to help chemo brain fog from taking its toll on your memory.

Some people find that writing down essential information helps them remember it better.

Others find that using a computer or phone calculator instead of trying to remember math problems helps them keep track of their finances.

If you’re having trouble remembering words, try writing them down on a piece of paper and carrying it with you.

You’ll probably want to avoid playing video games or watching movies that require a lot of concentration since chemo brain fog can make this difficult and frustrating for some people.

Forgoing these activities may be especially helpful if the chemo drugs are causing chemo brain fog.

Asking for help with everyday tasks like cooking, cleaning, shopping, or taking care of children can also be helpful, especially if the chemo drugs are causing chemo brain fog.

If you find yourself feeling frustrated because the chemo brain makes it difficult to do things you used to do quickly, try not to get discouraged.

Chemo brain fog can be frustrating, but it doesn’t mean that you’re losing your mind or that the chemo isn’t working.

Chemotherapy affects everyone differently, but most people find the chemo drugs don’t cause noticeable problems until they’re finished or almost done with treatment.

Chemotherapy can be a challenging experience, but there are ways to manage chemo brain fog symptoms.

By working with your oncologist, you can come up with a plan that helps you keep chemo brain fog from interfering with your life. If you’re struggling with chemo brain fog, don’t hesitate to ask for help.

Can chemo brain be prevented?

Preventing chemo brain fog is difficult because the cause of it is not fully understood.

However, there are a few things you can do to help minimize its effects, such as the following:

Keep a diary

Keeping a diary of chemo brain symptoms and the activities you do during chemo can help your doctor come up with a treatment plan that works for you.

Get enough sleep

Getting enough sleep every night is also crucial because chemo drugs make it difficult to get restful sleep, which only makes the chemo brain more intense.

Pace yourself

Don’t try to do too much at once–chemo brain fog can make it difficult to concentrate, and you may feel overwhelmed.

Take breaks often and allow time for your body and mind to rest.

Talk to your doctor about medication.

If the chemo drugs are causing brain fog, your doctor may prescribe medication to help you manage your symptoms

Concluding Thoughts

Chemo brain fog can be frustrating and make everyday activities seem more difficult.

However, by working with your oncologist, you can come up with a plan that helps you manage chemo brain fog symptoms.

There are also things you can do to help prevent chemo brain from taking its toll on your memory and daily life.

One of the most important things to remember is that chemo brain fog doesn’t mean chemo isn’t working.

Chemotherapy works well for many people, and chemo drugs do not cause noticeable problems until they’re nearly finished or completely done with treatment.

Keeping a diary can help your doctor come up with a plan that works for you.

If the chemo drugs are causing brain fog, your doctor may prescribe medication to help you manage your symptoms.

Remember that chemo brain fog is different for everyone, and try not to get discouraged if it takes some time to adjust. 

If you want to learn more about brain fog and overall brain health, head over to our blog and feel free to join our online community of mental health advocates and professionals.

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