After cancer treatment, you may have a hard time remembering, thinking, and paying attention. These are known as cognitive problems. Cognitive problems are common after cancer treatment. A cognitive problem that occurs after chemotherapy is often known as “chemo brain.” Some people describe it as feeling like “brain fog.” Symptoms can be mild and last only for a few months. Or they may be more severe and last longer. In some cases, they can cause problems with daily tasks, work, and relationships. Your cognitive issues will depend on your age, type of cancer, length and type of treatment, and other factors.

Researchers aren't sure why cancer treatment causes changes in thinking and memory. These changes are often linked to chemotherapy. But other treatments and things can contribute to cognitive changes. Hormone changes after cancer treatment, surgery, radiation, stress, anxiety, depression, anemia, pain, extreme tiredness, sleep problems, and some medicines may also affect cognitive issues. They may be, in some part, caused by the cancer itself. You may be more at risk for cognitive problems if you've had one or more of these types of cancer:

• Blood cancers (leukemia, multiple myeloma)
• Brain cancer
• Breast cancer
• Colon cancer
• Ovarian cancer

After cancer treatment, you may have trouble:

• Remembering things, especially details like names and dates.
• Learning new things.
• Multitasking.
• Paying attention.
• Concentrating and focusing on a task or something complex.
• Answering questions.
• Thinking or understanding information quickly.
• Reading.
• Thinking of a word you want to say.
• Solving problems.
• Making decisions.

Treatments may include:

• Medicine. Some kinds of medicine may help with cognitive problems. These include stimulants like modafinil and methylphenidate. Donepezil is another type of medicine used for dementia that may help. Your doctor will determine if medicine is right for you.
• Cognitive exercises. These are mental exercises that may help the brain work better over time. The training can be done on a computer. Your doctor may also suggest other things to try, such as biofeedback or mindfulness training, and refer you to specialists like an occupational therapist to help you with the cognitive changes.

If you're not sleeping well, not getting physical activity, or not getting good nutrition, these can make cognitive problems worse. Make sure to:

• Eat a healthy diet with plenty of fruits, vegetables, and whole grains.
• Exercise regularly. Ask your doctor what exercises are safe for you to do and how often to do them.
• Keep a regular sleep schedule, and tell your doctor if you have sleep problems.
• Don't use tobacco. Ask your doctor for help quitting.
• Limit or avoid drinking alcohol. Don't use other substances that may affect your ability to think clearly and sleep well.

• Write things down. Don't rely on remembering things. Write down things such as to-do items, upcoming events, and grocery lists in a notebook or on an app on your phone.
• Set reminders. Use your computer and phone to create reminders. Remind yourself of everything from appointments and daily tasks to when to take vitamins and walk the dog.
• Get rid of distractions. Noise, activity, and other people can make it harder to focus on something like reading or working on a task. Try to keep your environment quiet and calm when you need to concentrate.
• Get organized. Get in the habit of planning your day and keeping routines. This can help you stay on track without taxing your mental resources.
• Choose a spot for important items. Use this for things you commonly misplace or lose, such as keys. Put the items there every time you are done with them.
• Prioritize. Do the most important tasks at a time when your energy is highest and your thinking is clearest.
• Be patient with yourself. Keep in mind that “brain fog” is a common after-effect of cancer treatment. The medicines that help kill cancer affect the body in many ways.
• Ask for help. Accept help from loved ones for challenging tasks. Delegate daily tasks to lessen your list of to-do items.

Talk with your family and friends if you're having cognitive problems after cancer treatment. They can help you with daily tasks and give emotional support. You may also want to talk with other people who feel the same way. Your doctor can help you find a local or online cancer survivors support group.

Ask your doctor about your personal risk for cognitive problems based on your type of cancer, treatment, and other factors. Tell your doctor if your memory and thinking problems aren't getting better or are getting worse. They may want to check if you have depression or anxiety. These can make symptoms worse or make it hard to get better. Your doctor may also want you to keep a log of your cognitive problems to see what makes your thinking better or worse. Before a medical appointment, write down any questions you want to ask your doctor. Consider taking a friend or family member to your appointment so they can help you remember important information.