Long COVID Brain Fog: What is it and what can you do about it

Long COVID Brain Fog: What is it and what can you do about it

Having trouble thinking or remembering things after getting COVID? That might be a “long COVID brain fog”

It has been almost three years to date since we started our battle against SARS-CoV-2 or simply the COVID-19 virus, and we have seen how it affects people differently—some describe their experience as “just like the flu” while others got severely ill and unfortunately, there are some that even cost them their lives. 

"Brain fog" has been a common issue among COVID-19 patients. What makes it even more curious is how some patients experience this as one of the indicators of having “long COVID.” 

The Centers for Disease Control and Prevention (CDC) defines "long COVID" (or “Post-COVID Conditions” as called by the World Health Organization) as “a wide range of new, returning, or ongoing health problems that people experience after being infected with the virus that causes COVID-19.” CDC also mentioned that long COVID symptoms can be identified at least four weeks after infection since most COVID-19 patients get better within a few days to a few weeks.¹

People that are found to be at higher risk for experiencing long COVID are people who had severe COVID-19 illness and those who are unvaccinated. Long COVID may last for weeks, months, or sometimes even longer.

While COVID is generally perceived as a respiratory virus, it has shown effects on different systems of the body. Symptoms of long COVID vary with common symptoms including fever and fatigue. Additionally, there are others who experience respiratory and heart symptoms like difficulty breathing, cough, and pounding heart. There are also cases of digestive symptoms like diarrhea and stomach pain; joint or muscle pain; neurological symptoms such as headache, and dizziness, and; cognitive difficulties like brain fog among others.¹

Other names for long COVID or Post-COVID Conditions are: post-COVID-19 syndrome, long-haul COVID-19, and post-acute sequelae of SARS-COV-2 infection (PASC).


Now, let’s dive into "long COVID brain fog."

“Brain fog" (also sometimes referred to as "cognitive impairment") is not an actual medical term or diagnosis. However, the term has been used to describe a neurological symptom of feeling "sluggish, fuzzy, and not sharp" especially when thinking.² In other words, it is basically when you try to think of or remember something and then you just feel confused or have trouble focusing on what you are thinking.


According to Healthline, brain fog may come in the form of:

  • memory problems (or short-term memory)
  • lack of mental clarity
  • concentration issues
  • feeling "out of it"
  • headaches
  • confusion


Brain fog is not new or an exclusive COVID-19 symptom. In fact, we experience brain fog every now and then, even without contracting the virus. However, it has been observed that brain fog has become more common for COVID-19 patients because SARS-CoV-2 has neuro-invasive properties that can cause inflammation in the brain hinders. This inflammation then affects the neurons’ ability to communicate with one another.

While long COVID is more common in people who have had a severe experience of the virus, it is important to note that long COVID, including its varying symptoms, can also occur in people who had a mild case of the virus.

In an article released by Forbes.com at the beginning of this year, a study found that the neuro-inflammatory mechanisms of the virus can also cause “damage to brain cells” and “cognitive dysfunction” even to those who have had mild COVID.

The research also found out that “one in four COVID-19 patients had cognitive symptoms that lingered at least two months, even after mild infections. Patients’ symptoms included impairments to attention, concentration, memory and executive function, as well as slower information processing—all of which are also common among people who experience ‘chemo brain’ after cancer treatment.”³ 

Additionally, Healthline added that researchers have also identified that the COVID-19 virus can also cause microstructural changes in the hippocampus (considered the "memory center" of the brain) and other areas of the brain which can also contribute to cognitive impairments.²

Based on a study published in December 2020 by the National Library of Medicine (NLM), 28% of people who had lingering concentration problems due to the COVID-19 virus experienced these problems more than 100 days after their hospital admission.

Moreover, in another study from NLM, researchers found that out of 60 patients who recovered from COVID-19, 55 percent experienced neurological symptoms three months after their infection.


So how do you handle it?

Well, firstly, inform your doctor. Regardless of which symptom you are experiencing, the best route to take will always be to consult your doctor. Again, the effects of long COVID vary from patient to patient. If you're feeling anything you don't normally feel before contracting the virus, tell your doctor immediately so the symptom/s can be properly addressed.

Harvard Health Publishing recommends taking on activities that help improve cognitive functions such as thinking and memory:

  • Aerobic exercises
  • Healthy diet that includes live oil, fruits and vegetables, nuts and beans, and whole grains
  • Avoid alcohol and drugs
  • Healthy sleeping habits
  • Participating in social activities
  • Pursuing beneficial activities like listening to music and practicing mindfulness

Other cognitive or mental health problems.

While brain fog is one of the most common issues, there are other cognitive problems that COVID-19 may cause. In a study conducted by experts from Johns Hopkins, COVID-19 can also increase the risk for anxiety, depression, and other cognitive issues.

 “Cognitive impairment after acute coronavirus infection can have a severe impact on a person’s life. Long-haul COVID patients may experience changes in the way they think, concentrate, speak and remember, and these symptoms can affect their ability to work or even maintain activities of daily living,” Johns Hopkins Medicine said. 

 In addition, a study also showed that the most affected domains by COVID-19 were executive functions, attention, and episodic memory. The study also found a pattern in cognitive impairment in processing speed, inattention, or executive dysfunction.

Prevention is still better than cure.

The COVID-19 pandemic has been plaguing us for almost three years now; while some already think that this is the "new normal," we should not forget that there has never been anything like this. Scientists and health professionals alike are still conducting research because so much about it remains unclear.

For now, the best way to prevent contracting the virus and experiencing severe symptoms remains to be through availing of the COVID-19 vaccine, keeping a healthy lifestyle, and taking safety precautions.