"Brain fog” is not a medical term, but it may seem familiar or intuitive. It refers to what people feel in any condition that causes confusion, memory loss, difficulty finding words, and loss of focus or inability to concentrate. These problems affect their day-to-day functioning and diminish their quality of life.

Long COVID and Brain Fog

Brain fog has been identified as a common symptom among people with long COVID. The Centers for Disease Control and Prevention defines long COVID as a range of symptoms that can last weeks or months after an initial COVD-19 infection. Brain fog in people with long COVID develops and persists about 4 to 12 weeks after infection. In one recent study, symptoms reported by individuals with long COVID included difficulties with planning, decision-making, attention, processing speed, memory, and recall.

“Fatigue and cognitive impairment are the most debilitating symptoms of long COVID,” noted Durga Roy, M.D., with the Johns Hopkins School of Medicine, at a May 22 session (“Brain Fog: What is it Really?”) at the American Psychiatric Association’s Annual Meeting in New Orleans. She  noted that anxiety and depression associated with long COVID may also be contributing.

Recent research has found that brain fog can occur even if the person did not notice cognitive symptoms with the initial COVID infection and the illness was mild or asymptomatic. However, the symptoms were found to improve over time, about 6 to 9 months.

Treatments to help improve brain fog symptoms include cognitive-behavioral therapy (CBT), graded exercise therapy (building stamina gradually) and rehabilitation. There are no specific or FDA-approved treatments for COVID-related brain fog at this time, although several medications are being studied. As Roy noted in her presentation, more research is needed on brain fog and long COVID.

Brain Fog and Other Conditions

Brain fog is also associated with cancer and cancer therapies, fibromyalgia, chronic fatigue syndrome and lupus. It can also result from some medications, lack of sleep, and increased stress.

Brain fog associated with cancer or cancer treatment, sometimes referred to as “chemo-brain,” can have a significant impact on the person’s quality of life. Up to 75% of people undergoing cancer treatment experience cognitive decline during treatment; about 35% experience cognitive decline months or years later, Jon Levenson, M.D., with Columbia University Irving Medical Center, explained during his presentation at the APA Annual Meeting session. Levenson suggested it’s important for healthcare professionals to validate people’s experiences of cognitive problems, to provide reassurance as appropriate that it is not a progressive condition and not Alzheimer’s, and to acknowledge that problems may come and go.

He also identified steps that help, such as cognitive rehabilitation provided by neuropsychologists, occupational therapists, and speech therapists. Cognitive rehabilitation includes both efforts to restore function (improving performance through practice of isolated tasks) and strategies to help compensate (such as lists and organizers to help improve function). Low-intensity exercise and yoga, healthy eating habits, and mindfulness-based stress reduction can also help improve function and quality of life.