Brain Fog: When You Have Trouble Thinking Clearly

It happens to most of us at some point: we have trouble concentrating or remembering things. Is this something to be concerned about?

Illnesses like a cold, the flu or a migraine can trigger “brain fog,” and so can medications like antihistamines. The cognitive symptoms usually disappear when the disease ends or the medication wears off.  Cancer patients undergoing chemotherapy also report difficulty remembering, focusing and solving problems.

But these cognitive symptoms also occur frequently in long COVID – a potentially debilitating illness that can last for weeks, months or even years after a COVID infection.

While most people recover from a COVID-19 infection in about a week, in up to 30% of cases, symptoms linger three months later, which the World Health Organization defines as “long COVID.” Brain fog and other neurocognitive issues have persisted in some patients for at least two years.

Although more than 200 symptoms have been linked to long COVID, extreme fatigue and these cognitive deficiencies characterized as brain fog are among the most common:

• Difficulty paying attention
• Difficulty concentrating
• Difficulty remembering
• Difficulty solving problems
• Difficulty multi-tasking

These symptoms may result in:

• A sense of confusion
• Unclear thinking
• A sense of slowness
• Mood disorders

Research is under way to find effective treatments for long COVID, but until those emerge, medical professionals are grouping patients into symptom-based clusters – brain fog is one cluster – and investigating treatment and best practices within each cluster.­­

Is Brain Fog Affecting Your Daily Routine?

So what should you do if you have brain fog after COVID?

First, if brain fog is interfering with your daily activities, let your primary care doctor (or neurologist, if you have one) know about your symptoms. You probably will be referred to a neuropsychologist, who will perform an in-depth assessment of your cognitive and psychological functioning.

This assessment will identify both neurological issues (how the brain as an organ is working) and psychological symptoms (how this is affecting your cognitive, emotional and behavioral health), as the two can overlap in long COVID but require different treatment approaches.

Based on the results of this assessment, your neuropsychologist will make recommendations to your medical team.

Medical Treatments for Long COVID

Chemotherapy causes brain fog by inflaming neurons, which changes the way some cells behave. A COVID-19 infection can have the same inflammatory effect on the brain – even if the virus never infected a nerve. One study found that mice had high levels of inflammatory compounds in both the blood and fluid surrounding the brain and spinal cord following a mild respiratory case of COVID-19. The virus activated a type of human immune cell called microglia, and those cells remained reactive weeks later, leaving the brain struggling to keep up with some tasks, like making new neurons, which play an important role in memory and learning.

Despite this scientific understanding of brain fog’s cause, there are no medications currently authorized to treat it, although several studies are under way:

• Rivastigmine, which has been used to treat symptoms of patients with mild to moderate dementia, is now in trials for use with brain fog in long COVID.
• Researchers at Yale found that guanfacine, approved by the Food and Drug Administration in 2009 to treat attention deficit-hyperactive disorder, helped relieve brain fog when used in combination with another anti-oxidant. This potential treatment is very new, and testing has been limited to small cohort sizes.

Larger, placebo-controlled clinical trials will be needed to establish these or other drugs as bona fide treatments for post-COVID-19 neurocognitive deficits.

Lifestyle Changes To Relieve Long COVID

Whether or not you are prescribed medicine for your long COVID-induced brain fog, your medical team likely will recommend an anti-inflammatory diet and regular exercise because these are the most effective, proven treatments available.

It’s essential to reduce your intake of salt and inflammatory foods like saturated fat, sugar (in all its forms), and starches that the body quickly converts to sugar like rice, potatoes and white bread. Avoid packaged snacks and other highly processed foods as well as fried foods, which are high in saturated fat. Diets that are high in meat and dairy can also contribute to inflammation.

Instead, eat lots of fruits and vegetables along with and some nuts and whole grains – provided you already tolerate them. These foods are high in phytochemicals, which naturally reduce chronic inflammation.

Many long COVID patients also suffer from extreme fatigue, which can make even routine chores exhausting. But you should try to keep moving as much as you can because long COVID can leave you with fewer small capillaries – those tiny blood vessels that carry oxygen to the tissues. Aerobic exercise improves both vascular flow and lung capacity and causes the brain to release adrenaline into the blood – all of which can improve attention and concentration.

A number of scientific studies have associated a wide variety of exercises with improved brain function and relief from chronic fatigue. While the Centers for Disease Control and Prevention recommends adults exercise for 30 minutes a day, any movement counts. Walking is a great exercise.