In March 2020, the World Health Organization (WHO) declared a pandemic in response to the spread of the COVID-19 virus.

Since then, there have been over 33 million cases in the United States alone. Over the past year, medical professionals have been quickly working figure out what the symptoms of COVID-19 are.

Early symptoms that were observed included fatigue, shortness of breath, and fever. As the pandemic has gone on, new symptoms have been observed. This includes COVID tongue.

Patients with COVID tongue have bumps, white patches, and swelling on their tongues. Read on to learn more about this unusual COVID-19 symptom.

Along with the more well-known symptoms of COVID-19, some patients experience bumps, swelling, and inflammation of their tongue. This is known as COVID tongue.

People with COVID tongue might notice that the top of their tongue looks white and patchy, or that their tongue looks red and swollen. Additionally, many people with COVID tongue report experiencing a loss of taste and a burning sensation in their mouth.

Research documenting this possible COVID-19 symptom was published in The British Journal of Dermatology in September of 2020. But just like many things about COVID-19, there’s still a lot we don’t know about COVID tongue.

There have been other studies documenting COVID-19 tongue over the past several months, but more information is still needed to answer important questions about this symptom.

Scientists don’t know how rare COVID tongue is. In some studies, as many as one-quarter of patients hospitalized with COVID-19 had COVID tongue, but these studies were too small to make a general conclusion.

As more data from hospitals around the world comes in, we might be able to get a better idea of how common COVID tongue is.

Of course, most people with COVID-19 have mild or moderate symptoms and can recover at home. Even less is known about how many people in this group have developed COVID tongue. Many of them recover without seeing a doctor at all, so their symptoms are never recorded.

Even when people with mild or moderate COVID-19 do seek treatment, they’re often wearing masks or using telehealth for a video appointment. That makes it difficult for medical professionals to see their tongues and document any abnormalities.

Another reason that there are still so many questions about COVID tongue is that there are several possible causes. It’s not uncommon for illnesses and infections to cause changes to your tongue.

In fact, what looks like COVID tongue could easily be a symptom of a different viral or bacterial infection. Even when the bumps and swelling are clearly connected to COVID, there are many possible reasons. COVID tongue might be caused by:

  • A high number of ACE receptors in your tongue. ACE receptors are proteins found on cells in your body. When the virus that causes COVID-19, SARS-CoV-2, attaches to ACE receptors, it can get into your cells. You have a large number of ACE receptors in your tongue, which could lead to swelling when you have a COVID-19 infection.
  • Your immune system fighting COVID-19. When your immune system is fighting a bacterial or viral infection, it can cause swelling throughout your body. This could include the tongue swelling associated with COVID tongue.
  • COVID causing oral thrush. Oral thrush is a fungus in your mouth that can be caused by a number of infections. This might include COVID-19. Plus, oral thrush is a side effect of some of the medications used to treat COVID-19.
  • Changes to the surface of your tongue. Infections are known to sometimes lead to changes on the surface of your tongue that can lead to mouth ulcers and other symptoms. It’s possible COVID-19 can lead to this sort of change.
  • Dry mouth. COVID-19 can affect your salivary glands and cause them to secrete less salvia. This could lead to dry mouth. It’s well studied that dry mouth can lead to multiple other oral issues.
  • COVID activating oral herpes. The inflammation caused by COVID-19 can activate other viruses in your body. This might include the herpes simplex virus, which lays dormant in your body even when you don’t have symptoms. COVID could cause the herpes virus to activate and cause mouth ulcers.

COVID tongue could be caused by any one of these factors or by a combination of them. There’s also a chance that COVID tongue is sometimes caused by breathing tubes and other COVID treatments that could irritate your mouth and lead to a swollen tongue.

Until we know more about COVID-19, we won’t know the exact cause of COVID tongue.

It’s unclear whether COVID tongue is an early symptom of COVID-19 or a symptom that develops as the condition progresses.

No matter when it develops, it’s likely you’d also have other, more-common COVID-19 symptoms:

  • fever
  • cough
  • shortness of breath
  • fatigue
  • nausea
  • pain

Studies are being done to see if COVID tongue is ever an early or warning symptom.

Mild to moderate COVID-19

People with mild and moderate cases of COVID-19 are normally able to recover at home without medical intervention. Rates of recovery are also improving for people hospitalized with COVID-19 as doctors learn how to best treat the virus.

But since COVID-19 is still a new illness, we don’t know for sure what the long-term effects for people will be. Some symptoms of COVID-19 can linger for weeks, or even months.

Geographic tongue

While research on COVID tongue is still limited, we do know that viral infections can sometimes lead to a condition called geographic tongue.

This condition causes smooth red patches with white borders to appear on your tongue, and can last for months — or even years. Geographic tongue doesn’t generally cause pain or other issues, but flare ups can make it difficult to eat spicy foods.

It’s unclear whether COVID tongue is related to geographic tongue or whether COVID-19 can lead to geographic tongue. As more people recover from COVID-19 and more data becomes available, doctors will have a better understanding of COVID tongue and any possible long-term effects.

If you’ve had COVID-19 and are experiencing any mouth or tongue issues, talk with your doctor.

Some people with COVID-19 develop bumps, white patches, and swelling on their tongues. This is known as COVID tongue and is still being studied.

Right now, there are a lot of unanswered questions about COVID tongue. We don’t know how many people get COVID tongue or what causes it. More information about COVID tongue will be available as doctors learn more about COVID-19 and data is collected.