COVID Memory Loss and Brain Fog is Becoming More Common

It is too early to know all the long-term effects of COVID on the brain and nervous system. Some people complain of headaches, memory loss and confusion after COVID.

woman holding head brain fog symptom

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COVID-19 is a new version of an old virus called coronavirus. Most of the effects of COVID have been on people’s lungs, but there have also been effects on the brain and nerves (neurological effects). For now, doctors and researchers have been busy creating a vaccine and finding the best way to treat active COVID infections. It will take time to know what the long-term effects of COVID are on the brain, how long they last, and how they might be treated.

According to the National Institute of Neurological Disorders and Stroke (NINDS), for most people with COVID mild enough to recover at home, the only neurological symptom is a headache. However, for people admitted to the hospital, there have been more serious neurological symptoms including severe headache, dizziness, loss of taste and smell, and confusion. Less common, but more dangerous have been cases of COVID strokes, seizures, and severe brain or spinal cord inflammation.

How Acute COVID Infection Affects the Brain

An acute infection is a sudden and active infection. According to NINDS, COVID probably does not infect the brain or nerves directly. Inflammation and damage are caused by proteins called antibodies that the immune system makes in response to the infection. These antibodies may cause a severe immune system reaction that could cause brain or nerve swelling. There are also other ways COVID can cause neurological symptoms:

  • COVID mainly affects the lungs and causes oxygen levels to drop. The brain and spinal cord (central nervous system) require oxygen to function. Low oxygen levels can cause damage to the central nervous system. Without oxygen brain cells start to die.
  • Some research shows that COVID viruses can attack the cells in the walls of blood vessels and make them weak. This can cause microbleeds. In the brain, these microbleeds lead to mini-strokes.
  • COVID may also increase the risk for blood clots. A blood clot in a blood vessel that supplies part of the brain can also cause a mini-stroke.
  • A large bleed or large blood vessel clot in the brain can cause a full-blown stroke with permanent brain damage.

    common covid symptoms

    Common COVID symptoms don’t typically include neurological symptoms, but brain fog and memory loss can occur because of “long COVID.”

What About Long-Term Neurological Symptoms Like Brain Fog?

Symptoms that continue after acute COVID infections have been called “long COVID.” Long COVID neurological symptoms may occur more commonly in people who have been hospitalized for COVID, but they are also reported in people with milder COVID.

The main symptom of long COVID is fatigue. Other people complain of COVID memory loss and COVID brain fog. Brain fog is not a medical term and may mean different things to different people. Brain fog can include headaches, sleep problems, confusion, and memory loss. Possible causes include:

  • Extreme fatigue may cause brain fog.
  • There may be some brain damage from mini-strokes or microbleeds.
  • There may be long-term inflammation in the central nervous system.
  • Brain fog symptoms may be caused by PTSD or depression.

COVID mini-strokes and microbleeds are more likely in people over age 70. COVID has killed more Americans than Viet Nam, Korea, and World War I combined, and severely disrupted all our lives, so depression or PTSD could certainly be a cause.

Is There Any COVID Brain Fog Treatment?

Until we have more time and more studies, there are more questions than answers. We don’t know how long brain fog lasts after COVID or how long fatigue lasts after COVID. Until we know more, there is no known treatment for long COVID neurological symptoms. The best thing to do is tell your doctor about your symptoms and work with your doctor to find what works best for you.


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Chris Iliades, MD

Chris Iliades has an MD degree and 15 years of experience as a freelance writer. Based in Boothbay Harbor, Maine, his byline has appeared regularly on many health and medicine … Read More

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