Chemotherapy brain fog (chemo brain) happens when coping with cancer or cancer treatment affects your ability to remember and act on information. Usually, chemotherapy brain fog is a short-term issue, but some people may have symptoms for months after they’ve finished treatment. There isn’t a cure for chemotherapy brain fog, but medication, therapy and activities may help.
Chemotherapy brain fog, or chemo brain, is feeling as if you can’t think as quickly and as clearly as you did before you had cancer or received cancer treatment. Healthcare providers may refer to this condition as chemotherapy-induced cognitive impairment or cancer-treatment-related cognitive impairment. But healthcare providers have learned that people develop cognitive problems before, during or after receiving treatment.
Most of the time, chemo brain is a short-term issue, but some people may have the symptoms for months after they’ve finished treatment. Healthcare providers can’t cure chemotherapy brain fog, but they can recommend medications or therapy and activities that may help lift the fog of chemo brain.
Chemotherapy brain fog affects cognition. Cognition is how we think, how we remember information and our ability to concentrate. Cognition issues related to cancer treatment may show up in small ways. Many times, people can manage everyday tasks, but feel those tasks require more concentration and take more time. Sometimes, chemo brain fog makes people feel self-conscious about their cognitive issues, so they become more isolated. Chemotherapy brain fog often affects people’s ability to function in the workplace.
Some studies show people with chemo brain have depression. Sometimes, people get angry or frustrated because they can’t do things as well or as quickly as they once could.
Healthcare providers who study cancer treatment and cognition estimate that 25% to 30% of people who have chemo brain develop symptoms before they start cancer treatment. About 75% of people receiving cancer treatment tell their healthcare providers they having issues with memory, concentration and their ability to complete tasks.
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Issues with memory and executive function are common chemo brain symptoms. In this case, memory is being able to remember what people tell you and things you already know like addresses and names. Executive function is your ability to manage your time and make decisions. Symptoms may include:
Despite its name, chemotherapy brain fog may happen for several different reasons
There’s no single test for chemotherapy brain fog. Healthcare providers may do blood tests to rule out conditions that may cause brain symptoms.
Healthcare providers may recommend several therapies or activities that may reduce some chemotherapy brain fog symptoms, including:
Your healthcare providers choose the treatments that they expect will kill or slow your cancer. They know some of those treatments may affect your memory and your ability to concentrate. They’ll work with you to reduce those side effects as much as they can while effectively treating your condition.
Healthcare providers have found a few risk factors, most of which you can’t control. For example, age and underlying medical conditions may increase your risk of developing chemotherapy brain fog before, during or after receiving cancer treatment.
People may have chemo brain for varying amounts of time. Chemo brain may last for several months to several years.
First, treat yourself with patience and gentleness. There’s nothing easy about cancer and cancer treatment. You may need time to recover physically, mentally and emotionally from the challenges of having cancer and coming through cancer treatment, including chemotherapy. Here are some suggestions that may help you cope with chemo brain:
As a cancer survivor, you’ll probably have regular checkups with your healthcare provider so they can evaluate your overall health. That said, if you notice your chemotherapy brain fog symptoms suddenly get worse or you have new symptoms, contact your healthcare provider right away. That way, they can evaluate whether your new or worsening symptoms are signs of another medical issue.
You may not be able to avoid chemo brain, but you may feel better about your situation if you know why and how chemotherapy brain fog happens. The National Cancer Institute suggests the following questions:
A note from Cleveland Clinic
If you have cancer, having chemotherapy brain fog may not make the top of your worry list. Your priorities may be, 1) understanding your cancer diagnosis, 2) understanding and preparing for the proposed treatment and 3) completing treatment with the hope that you no longer have cancer. In other words, you’re managing many challenges. Even so, don’t downplay symptoms like having trouble making decisions, focusing on tasks and remembering information. Like actual fog, chemotherapy brain fog may start slowly. You may not notice changes right away. When you do, talk to your healthcare provider. Chemo brain can affect your quality of life. Your healthcare provider will evaluate your situation and suggest ways to ease chemo brain symptoms.
Last reviewed by a Cleveland Clinic medical professional on 09/06/2022.
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