Brain Fog After COVID-19: Why It Happens and What You Can Do

According to multiple studies, those with long COVID-19 experience a variety of symptoms that may include brain fog.

Not only do these reports shed light on how the COVID-19 virus can impact our cognition, but they also illuminate the fact that anyone—no matter their COVID-19 history—can experience persistent brain fog.

If you feel you’ve had brain fog after COVID-19, the Aviv Clinics team is here to help you navigate through that. Stay educated with this essential guide to give yourself the best chance at getting back to optimal health.

As you’re reading through this, keep in mind:

What Is Brain Fog?

Brain fog is a term that describes slow or sluggish thinking. Someone with brain fog may experience confusion, forgetfulness, and/or a lack of mental clarity.

We all experience brain fog from time to time. Perhaps you didn’t get enough sleep the night before, took an antihistamine, or had a cold that made you feel unfocused or disoriented. In cases like these, you can simply rest and feel like yourself in no time.

But sometimes, individuals experience brain fog that lingers even beyond six months after having COVID. This has been one of the main symptoms of post-COVID.

Is Brain Fog a Symptom of Long COVID?

Yes, brain fog is a common symptom of long COVID—the CDC lists brain fog under its neurological symptoms. Brain fog from COVID-19 doesn’t necessarily need to manifest on a substantial level; it can be subtle. One study notes participants who didn’t notice their brain fog still performed poorly on attention and memory tasks.

Why Does COVID-19 Cause Brain Fog?

Stanford Medicine researchers note brain fog from COVID-19 emulates the same cognitive issues caused by cancer chemotherapy (“chemo brain”). In both cases, excessive inflammation damages the brain cells and processes.

Aviv physician Dr. Mohammed Elamir, MD, FACP, further explains there is a link between:

  • Where the COVID-19 virus attacks the brain
  • How that impacted location in the brain affects long COVID symptoms

There are four main ways COVID-19 can attack the brain:

  • Direct brain invasion: The virus travels through the nose and into the insula—which oversees memory and executive function through its connection with the prefrontal cortex.
  • Blood vessel injury: The COVID-19 virus may harm blood vessels that feed blood to the brain.
  • Dysregulated immune response: Damaged blood vessels caused by COVID-19 can slow down the growth of cells, impacting the brain’s immune response.
  • Cellular dysfunction: COVID-19 can trigger cell damage. This slows down the body’s response rate to infection, leading to high inflammatory conditions.


Is My Brain Fog Related to COVID-19?

If you notice your cognition has not been the same since your COVID-19 infection, we recommend speaking with a physician. Your body and health background are entirely unique from other people’s. Therefore, it’s important to discuss your lingering symptoms with a healthcare professional to assess whether your brain fog is indeed due to long COVID.

The certified physicians at Aviv Clinics assess the following four areas to diagnose long COVID. Walking through these four areas enables your physician to provide the holistic approach your health deserves.

  • Physical symptoms: Fatigue, cough, loss of taste or smell, labored breathing, joint or muscle pain, etc.
  • Cognitive and psychological symptoms: Brain fog, anxiety, depression, sleep disturbances, headaches, etc.
  • Lung symptoms: Shortness of breath, chest pain/tightness, etc.
  • Cardiac symptoms: Heart palpitations, elevated blood pressure, decline in oxygen saturation, etc.

How Can You Minimize Post-COVID Brain Fog?

Minimizing post-COVID brain fog involves engaging in activities known to improve memory and thought processes. These activities may include:

  • Exercising
  • Getting adequate sleep
  • Eating a well-balanced diet

Addressing Long COVID Symptoms

Multiple studies reveal, as part of a comprehensive treatment program, hyperbaric oxygen treatment (HBOT) may help in mitigating long COVID symptoms. From clinical and qualitative evaluations of HBOT patients, researchers conclude there is hope that HBOT can address some of the common symptoms such as fatigue and brain fog.

Aviv Clinics’ team of certified physicians takes a three-step approach to their long COVID treatment:

  • In-depth medical assessment: Conducting comprehensive testing (physical, cognitive, and neurological) and brain imaging
  • Tailored treatment program: Creating a customized treatment plan based on your test results
  • Post-treatment assessment: Administering second round of testing to unveil findings/progress

Learn more about Aviv’s long COVID approach.

How Long Does Post-COVID Brain Fog Last?

As everyone’s bodies are different, there is no set time limit to COVID-19 brain fog. Some research studies indicate that most patients recover within six to nine months, with others experiencing brain fog for two years or more.

Dr. Mohammed Elamir, MD, FACP, says how long it takes for brain fog to go away depends on how invasive the virus is in your body:

“[…] the amount of real estate that those microvascular changes are occupying will probably dictate how long [symptoms] will last.”

The Bottom Line

Brain fog from COVID-19 can be difficult to live with. If you or a loved one suspects COVID-19 has left lingering cognitive issues, contact Aviv Clinics. Our team will offer the resources you need to learn more about how our team of physicians treats long COVID symptoms. Feeling your best cognitively and physically starts with us.

Long COVID Explained: The Symptoms and Why They Stick Around

Last updated: January 15, 2024

Millions of individuals who have tested positive for COVID-19 continue to experience ongoing health issues, clinically known as long COVID. If you’re one of these people, the Aviv team is here with research-backed information on what this means and what you can do.

While there is still uncertainty surrounding COVID-19 complications and their long-term side effects, there have been extensive studies conducted that offer insight into:

  • Post COVID symptoms
  • How long COVID can impact your body and lifestyle
  • Treatment methods that can help mitigate long-haul COVID effects

Below, we provide all the details you need to attain a holistic understanding of how long COVID impacts your body and promising treatment plans that can help you get back to optimal health. As you’re reading through this, keep in mind:

  • Each person has a unique experience with COVID-19.
  • Therefore, speaking with a doctor is an essential first step.
  • Several alternative terms are used for long COVID, such as post-COVID, long-haul COVID, post-acute COVID, and chronic COVID.

How the CDC and WHO Define Long COVID

  • The Centers for Disease Control and Prevention (CDC) defines long COVID as a condition where individuals experience long-term effects of COVID-19.
  • The World Health Organization (WHO) defines long COVID as persistent symptoms more than 3 months after the acute infection, that continue, not relapse, that have been reoccurring and there is no other explanation for those symptoms.
  • Anyone who has been infected with COVID-19 can develop long COVID. Approximately 30% of COVID-19 patients report having symptoms of long-haul COVID.

The numbers of people affected long term are high

The WHO had a definition of long COVID over two years ago. That means, from nearly the beginning, these health organizations studying the virus were seeing long-term side effects and symptoms of impairment from having COVID-19.

You aren’t alone if you don’t feel like yourself after having COVID-19.

  • Approximately 30% of COVID-19 patients report having symptoms of long-haul COVID.
  • 20-50% of patients with 1 or more features 3-6 months post COVID, receive a long COVID diagnosis.
  • 11-20% of children have lingering symptoms at 14 weeks post COVID.

For a comprehensive understanding of what long-haul COVID is, let’s flesh out the differences between COVID and long COVID:

Acute COVID:

  • Individuals experience COVID-19 symptoms for up to four weeks, starting from the onset of illness.
  • Subacute is where COVID-19 symptoms are noticed up to 12 weeks, and the virus can still be found in the body.


  • Individuals experience COVID-19 symptoms for an average of three months from the onset of illness.
  • Long-haul COVID symptoms may begin after initial recovery from acute COVID or persist from the initial illness.
  • Long COVID symptoms cannot be explained by an alternative diagnosis.


Understanding the Symptoms of Long-Haul COVID

The Aviv medical staff primarily explores the four key areas from this long-haul COVID symptoms list to diagnose long COVID.

Physical Symptoms:

  • Fatigue
  • Dyspnea (labored breathing)
  • Chest pain or tightness
  • Cough
  • Dysgeusia (loss of taste)
  • Anosmia (loss of smell)
  • Joint or muscle pain

Cognitive & Psychological Symptoms:

  • Memory decline
  • Attention and concentration difficulties
  • Brain fog
  • Anxiety
  • Depression
  • Sleep disturbances
  • Headaches
  • Generalized disabling pain
  • Lung Symptoms
  • Shortness of breath
  • Chest pain or tightness

Cardiac Symptoms:

  • Myocarditis (inflammation of heart muscles)
  • Heart palpitations
  • Shortness of breath
  • Elevated blood pressure
  • Drops in oxygen saturation

If you are experiencing long COVID symptoms,
contact our team of certified medical professionals today – click here.


The Hard Truth: Long COVID & Brain Injuries

COVID-19 essentially impacts the brain. This is why the majority of long COVID symptoms are cognitive and may lead to brain injuries, depending on how severely your body gets affected by the virus.

According to Dr. Mohammed Elimar, MD, FACP, although there are no patterns between the severity of COVID-19 and the likelihood of receiving long COVID, there are patterns between:

  • Where the virus attacks in the brain
  • How that location in the brain impacts long COVID symptoms

Long Covid Impact On Brain.

Here are four ways that connection can manifest:

1. Direct Brain Invasion

The COVID-19 virus travels through the nose, into the olfactory sensory neurons, and into the frontal lobe of your brain called the insula. The olfactory neurons manage taste and smell, while the insula oversees memory and executive function. Depending on where the virus attacks and the level of damage it creates, an individual may experience prolonged COVID symptoms.

For example, when the virus significantly attacks your olfactory nerves, this may induce a loss of taste and smell. This is why these symptoms are such a strong indicator of the virus.

2. Blood Vessel Injury

Studies show COVID-19 can destroy blood vessels that feed blood to the brain. As the virus circulates throughout your bloodstream, the inner blood vessel lining is susceptible to damage. When the inner lining deteriorates, this allows the virus to: Seep into the tissues, or inhibit blood flow to the brain. Both can cause brain injuries. And depending on where those injuries occur, specific brain functions (memory, concentration, etc.) may decline more rapidly than normal.

3. Dysregulated Immune Response

Damage to the inner blood vessel lining can also inhibit the growth of cells—the exact opposite of what our immune system should be doing. Dysregulated immune responses are common in those with severe cases of COVID-19.

When the body cannot adequately produce a normal immune response, it either: Underreacts to foreign invaders, causing viruses to spread quickly; or oerreacts to foreign invaders, causing the immune cells to attack even healthy cells, tissues, and organs.

4. Cellular Dysfunction

On a cellular level, COVID-19 can affect metabolic function through the mitochondria. This cell damage slows down the body’s response rate to infection, leading to high inflammatory conditions.

So how long will patients have to deal with COVID symptoms?
According to Dr. Mohammed Elimar, MD, FACP, the answer isn’t available.
But a key guiding factor is the extent of blood vessel damage.
Dr. Elimar further explains:

“There’s still a lot to learn about how [mitochondrial dysfunction] will last but it will probably be tied to the level of microvascular change or blood vessel damage. The more blood vessel damage you have, the more [long COVID symptoms] you’re likely going to have. Also, the amount of real estate that those microvascular changes are occupying will probably dictate how long [symptoms] will last.”

Aviv Clinics’ Treatment for Long COVID Symptoms

Long COVID is a complex disease.
Finding a treatment plan that will work for you may take some time.
Because there is no one-size-fits-all approach, speaking with a medical professional is essential.

The right physician will take a holistic approach. Due to the complexity of long COVID, it’s important to find a treatment program that:

  • Is rooted in data and research
  • Offers a comprehensive assessment process
  • Connects you with a diverse medical team


Aviv Clinic’s team of certified physicians achieves all of the above to ensure you’re being provided with a tailored treatment plan that works for you. We connect our patients with a team of physicians, neuropsychologists, physiotherapists, nurses, and more to provide a multidisciplinary health plan – The Aviv Medical Program.

Our post-COVID symptom treatment plan can be broken down into three parts:

  • In-depth medical assessment:
    Leveraging advanced brain imaging, our clinical team conducts physical, cognitive, and neurological exams to gain a thorough understanding of your health.
  • Tailored treatment program:
    Based on your assessment, our medical team crafts a personalized treatment plan, based on the results of your assessments, that includes hyperbaric oxygen therapy sessions, brain and physical training and a nutritional regimen designed to maximize the body’s healing process.
  • Post-treatment assessment:
    Our team initiates another round of tests to assess your progress and unique findings on any cognitive and physical improvements.

Watch Patrick’s Successful Journey in Fighting Long COVID


First Long COVID treatment backed by clinical trials – help heal the brain to reduce or eliminate the symptoms of long COVID

The Aviv Medical Program is backed by extensive clinical research.

The most recent study confirmed that the COVID-19 virus can cause chronic brain injury affecting regions of the brain responsible for cognitive function, mental status and pain interpretation.

In the published study, patients treated with the Aviv protocol had significant improvement in their global cognitive function and cognitive improvement in the damaged brain regions responsible for attention and executive function. Significant improvement was also demonstrated in the energy domain, sleep, psychiatric symptoms and pain interference. The beneficial effects of the unique treatment protocol can be attributed to neuroplasticity and increased brain perfusion in regions associated with cognitive and emotional roles.

Read more about the Aviv Medical Program for Long COVID

Dr. Shai Efrati of summarizes the results of a study by saying:

“HBOT can induce neuroplasticity and improve cognitive performance, psychiatric state, assist with fatigue, aid sleep and relieve pain symptoms for patients suffering from post covid 19 condition. The beneficial effect can be attributed to increased brain perfusion and brain plasticity in regions associated with cognitive and emotional roles. HBOT can repair brain network connectivity and activity, and improve cardiac functions in post covid patients suffering from reduced GLS.”


WebMD recently published the research of Dr. Efrati, noting the clinical trial that began in December 2020 shows great potential for Long COVID patients whose issues are connected to brain tissue damage.

Maximize Your Health and Performance with Aviv

Though COVID-19 may have brought ongoing health challenges, the Aviv team is here to help you and your loved ones get back to optimal health. Aviv delivers a personalized protocol to enhance your mind and body and feel like yourself again.

Learn more about our team, contact our clinic to schedule a free phone consultation. Maximizing your health and performance begins with Aviv.


Cognitive Impairment & COVID-19: What We Know So Far


There’s a lot that we still don’t know about COVID 19, especially when it comes to the long-term effects. However, emerging research suggests a troubling new link between the Coronavirus and long-term neurological dysfunction. Many “COVID long-haulers” continue to experience headaches, dizziness, fatigue, and brain fog even weeks after recovering from the Coronavirus. Research also suggests links between the virus and increased risk for strokes, which is concerning for older adults or anyone who already had an increased risk.

If you’ve been feeling lost and dazed since recovering from the Coronavirus, you’re not alone. But don’t despair. In this article, we’ll address the potential neurological effects of COVID-19, along with our best advice for COVID long-haulers.


What is a “COVID long-hauler”?

“COVID long-hauler” is a new term used to describe the growing number of people who continue to experience symptoms of the Coronavirus weeks after recovering. Common complaints among long-haulers include respiratory problems like a persistent cough or shortness of breath. Neurological problems are also common, including headaches, fatigue, loss of taste/smell, and the now-infamous “Covid brain fog”.

Long-haulers are a diverse group, and anyone can become one, young or old. It’s not unusual for someone to report feeling like they’re “in a fog” or “stuck in a daze” even weeks after testing negative for the virus. Some people may be plagued by COVID fatigue or headaches, while still others can’t taste their favorite foods.

You don’t need to have been hospitalized to be a COVID long-hauler, either. Even mild cases can lead to these unpleasant after-effects, which is why you still don’t feel like your old self even after a minor bout with the virus. It’s unclear exactly why some people become COVID long-haulers while others experience no ill effects. But researchers are working hard to gain a greater understanding of the risk factors involved.


How COVID affects the brain

Did you know that when it comes to COVID, losing your sense of smell is actually a neurological problem? It’s true. The Coronavirus can affect the olfactory nerve connecting your nose to your brain, which inhibits your sense of smell. It was one of the earliest signs that COVID could affect the brain. While we still need more research to determine the full extent of COVID’s neurological effects, preliminary studies have revealed a connection between the virus and impaired cognitive performance.

In the study, a group of COVID-19 patients between the ages of 30 and 60 underwent a series of neuropsychological tests to assess various functions of their brains, including memory function, processing speed, and executive function. The COVID-19 patients experienced inhibited cognitive function when compared to a healthy test group, and they especially struggled with sustaining attention on the tests, providing us with evidence that the “COVID brain fog” is a real phenomenon.

Further studies have also provided us with links between COVID and headaches and COVID and strokes, giving us a greater understanding of how the virus can impact the brain.


The inflammation connection

Interestingly, COVID patients also exhibit high levels of inflammation in their blood. That’s not surprising since inflammation is one of the immune system’s natural responses to threats. In low levels, inflammation is a good thing; it’s a sign that your body is addressing the problem as intended. But as with everything in life, balance is key, and excessive inflammation can wreak havoc on your health.

One of the symptoms associated with coronavirus is a “cytokine storm”, an overactive immune response that skyrockets inflammation levels. Cytokine storms have been associated with reduced oxygen in the blood and other respiratory problems caused by COVID-19. They’ve also been linked to neurological problems, like brain fog, fatigue, or the stabbing headaches associated with the virus.

Covid and inflamation

COVID and Strokes

While it’s still unclear exactly why COVID increases the risk of ischemic strokes (blood clots) in some people, inflammation could play a part. Chronic inflammation has long been linked to an increased risk of stroke, which could explain why the aging population is more susceptible.

Picture two highways. One highway is smooth and freshly paved without any potholes or blemishes. It’s easy for traffic to flow through this highway on a consistent basis, and traffic jams are uncommon. On the other hand, the second highway is littered with potholes, cracks, and closed lanes, all of which make it difficult for traffic to flow even on a good day. Now, which highway do you think will fare better when a snowstorm strikes?

The highways in this analogy are your blood vessels, and the flow of traffic is your blood cells. The snowstorm is, of course, COVID-19. Having high levels of inflammation in your body makes it easier for the blood to clot, which can ultimately lead to strokes. This is also why those with pre-existing conditions are hit hard by the virus — because their immune systems are already inflamed from fighting other problems.


How to combat inflammation

Because COVID patients almost always exhibit higher levels of inflammation in their blood, having low inflammation levels in your body can help combat the severity of the virus. Eating a clean diet, exercising regularly, getting plenty of sleep, and avoiding stress keeps inflammation levels low, which can help COVID long-haulers find relief. Avoiding stress is especially key, although that’s often easier said than done.

If you’re feeling stressed because of the pandemic, you’re definitely not alone. If the constant barrage of information from the news and social media is stressing you out, try unplugging for a while. Fire up the iPad for a chat with your grandkids, or head outside for a (socially-distanced) walk in the fresh air. While it’s important to stay informed, it’s also important to take care of your mental health.


Could getting vaccinated help a COVID long-hauler?

What about the Coronavirus vaccine? If you’re a COVID long-hauler plagued by brain fog or headaches, could getting vaccinated provide relief? Unfortunately, probably not. The purpose of the vaccine is to train your body’s immune system to fight against the Coronavirus. It’s meant to be used as a preventative measure. It’s not a cure, and it’s not a way to mitigate the virus’s after-effects. That’s no reason not to get vaccinated, however.

Even if you’ve already contracted the virus, the vaccine can prevent you from getting it a second time, which can minimize your risk of suffering long-term side effects. And if you’ve never contracted the virus before, getting vaccinated can ensure that you never have to deal with long-term side effects in the first place.

covid 19 vaccine

When to see a doctor about your long-term Coronavirus symptoms

If you’re struggling with long-term COVID neurological symptoms, you don’t need to suffer alone. Whether you’re being plagued by fatigue, brain fog, dizziness, headaches or loss of taste, any problem that impacts your quality of life is worth bringing up to your doctor.

Although your doctor may not have all the answers yet, they’ll do everything they can to help you cope with your symptoms. There’s also the possibility that your symptoms may not be caused by COVID at all, but by another health condition instead. Never hesitate to seek help when you need it, especially when it comes to your cognitive well-being.


The bottom line

While we still need more research to determine the full extent of the Coronavirus — especially when it comes to long-term symptoms — anyone of any age can minimize the damage caused by COVID simply by practicing healthy lifestyle habits and keeping your inflammation levels low. Taking care of your body inside and out is crucial not just for fighting COVID, but for any health condition you may encounter.

You can also minimize your chances of contracting the virus by continuing to follow the CDC guidelines of mask-wearing, social distancing, and getting vaccinated when you can. Above all else, staying calm and optimistic is one of the most important things you can do in the face of the pandemic. So do your best to stay positive.