‘Chemo brain’ is real, but there are ways to ease it

By the time she finished her second round of chemotherapy for breast cancer, Shannon Colleary says her brain felt foggy.

“I had no short-term memory at all,” says Colleary, 57, a screenwriter in Los Angeles who finished treatment in October 2021. “I’d think, ‘Why am I in this room? … Who is this person that just said hello to me? Where do I know her from?’ Then I’d pretend to know the person, but often left the interaction still uncertain of who they were.”

"Empty" is how Justin Schuster, 19, of Rye Brook, N.Y., describes his brain since he completed treatment for Hodgkin's lymphoma in April. "My thoughts aren't processing," says Schuster, who left Lehigh University last December after discovering a swollen lymph node just above his collar bone. "I can't find the word, and I forget what I'm trying to say."

What both Colleary and Schuster describe is often called “chemo brain,” shorthand for a debilitating medical condition characterized by loss of word retrieval, memory and executive function, and an inability to concentrate. Physicians call it cancer-related cognitive impairment (CRCI), and research indicates it affects about 75% of cancer patients during treatment, with 35% reporting persistent symptoms after treatment ends.

Why some people get the condition and others don't, and why some have symptoms that persist for years while others' symptoms are resolved in a few months remain puzzling.

But Arum Kim, director of the Supportive Oncology Program at NYU Langone's Perlmutter Cancer Center, urges people to communicate with their medical team about cognitive changes.

“Really good, calm communication with your treating oncology team is important because there are things that we can do for it — if we know about it,” she says.

Jeanne Mandelblatt, inaugural director of the Georgetown Lombardi Institute for Cancer and Aging Research, believes that inflammation plays a part.

"Cancer treatment kills cancer cells, but it also causes damage to cells that can accelerate aging and increase inflammation, including inflammation in the brain. That can affect cognition," says Mandelblatt, who leads Thinking and Living With Cancer, a 15-year longitudinal study focusing on aging breast cancer patients and cognitive impairment.

But "chemo brain" is a misnomer, she adds, because patients experience cognitive impairment from immunotherapy and hormone therapy as well as chemotherapy. "It is not all one thing, but it is a real phenomenon and people have cognitive problems that interfere with their lives," she says.

Chemo brain probably also kicks up simply because of the cancer itself.

"When people are going through cancer and recovering, they're experiencing a lot of other problems that can impact their functioning but don't necessarily impact their brain. There's a really high rate of insomnia in this population. There can be high rates of anxiety and depression, there can be major lifestyle changes. And those can make you less effective than you were before," says Nicolette Gabel, division director of rehabilitation psychology and neuropsychology at the University of Michigan's Department of Physical Medicine and Rehabilitation.

Colleary says the crushing depression she experienced during treatment was even worse than her short-term memory loss.

“It became very clear to me that the chemo drugs had killed every positive hormone in my brain,” she says. “Dopamine, serotonin, oxytocin, and endorphins simply did not exist. I became nihilistic at times, thinking ‘What’s the point of life? It’s too dangerous, lonely and sad.’”

Neuropsychologists such as Gabel and Eric Zhou, an assistant professor at Harvard Medical School who specializes in disease recovery, say treating chemo brain requires a multipronged approach.

"It is a combination of cognitive retraining, mindfulness practices to help reduce stress [and] improve things like sleep and relaxation and take down that kind of high-level cortisol stress that goes on when people are going through these changes," Gabel says.

Zhou urges patients to speak to their doctors as soon as possible about cognitive symptoms. A recent study showed that patients' symptoms improved with the following interventions:

Exercise: In a study of more than 500 breast cancer patients, those who exercised for 150 minutes a week maintained cognitive function similar to a control group of those without cancer, says Michelle C. Janelsins-Benton, study author and associate professor at the University of Rochester Medical Center.

"Individuals who were physically active at the time of their diagnosis, even if they didn't maintain that during treatment, had better cognitive maintenance, compared to those that were not physically active prior to treatment," Janelsins-Benton says.

She speculates that exercise combats inflammation in the body, which could be a contributing factor. In another study, Janelsins-Benton found that moderate exercise also helps patients maintain attention span. "This needs further study, but I think it's a very promising benefit of exercise," she says.

Cognitive behavioral therapy (CBT): Resetting thought patterns and behavior can improve symptoms and make life easier, Zhou says.

"If you are very forgetful, creating a very structured home environment so you have a specific place for things will be very helpful," Zhou says. "Using calendars, especially those on our phones or smartwatches that can ring alarms can prompt behavior."

Since being treated for Hodgkin's lymphoma when she was 19, Diana Pernicano, 29, a nurse from Yorktown Heights, N.Y., writes everything down. Her absentmindedness was once so bad that she was asked to resign from her first nursing job because she often forgot critical information.

"I was so embarrassed," she says. "Luckily I was able to refocus and get another nursing job I love that I have been at for nine years."

A type of CBT called memory and attention adaptation training is especially effective, Gabel says, and is something that can easily be practiced by patients at home.

Sleep: A lack of sleep “amplifies the physiological changes that are occurring for somebody who has chemo brain,” Zhou says. If you’re battling sleepless nights, consult your physician about trying CBT, which is considered the best method for addressing insomnia. Zhou says techniques might include adjusting bed times, making your bedroom more restful and “sleep restriction,” which involves limiting your time in bed only to those hours spent sleeping — not watching TV or reading or playing on your smartphone.

Mindfulness: Meditation, deep breathing and yoga can improve cognitive complaints, according to a small study of breast cancer patients. “We’re not sure why this helps, whether it’s a mind-body connection, or because these things are just good for us in general,” Zhou says.

Psychostimulants: Although there is not yet clinical evidence for their effectiveness, drugs such as Adderall may help. “Folks who are having a lot of trouble with cognitive fatigue and attention can find a significant effect from these drugs,” Gabel says.

Fear of cognitive impairment may lead cancer patients to opt out of treatments, but they shouldn't, Gabel says.

"All of this can sound very scary to folks, and I worry that people will turn down treatments that could be curative," she says. "There are survival rates for cancer now that 20 years ago would have been off the table. It's not guaranteed that chemo brain is going to happen, and if it does, there are ways that we can address it."

No Food and Drug Administration-approved medications are available for chemo brain, although Mandelblatt predicts it won't be long before physicians can offer pharmaceutical solutions to their patients.

"We are making some progress, and I expect that already approved drugs will be repurposed for chemo brain," says Mandelblatt, noting that studies in mice show promise.

One such study showed that Cisplatin, a widely used chemotherapy drug, alters the sphingolipid metabolism in a mouse brain's hippocampus (where memory is stored) and that plays a key role in chemo brain, says the study's author, Daniela Salvemini, the director of Institute for Translational Neuroscience at St. Louis University School of Medicine.

Salvemini's team then administered Fingolimod and Zeposia, drugs already approved by the FDA to treat multiple sclerosis, and discovered that they could block the development of chemo brain in mice.

Although human trials are needed, Salvemini says, “I think this could be a revolutionary approach to the treatment of cancer patients and cancer survivors. We are very excited about this. Chemo brain is very real. Though it does not affect everybody, for those who it does, it has a real impact on their lives.”