COVID tongue is real: Here's how to treat it

“COVID tongue,” an enigmatic yet increasingly recognized presentation of the COVID-19 infection, has piqued the interest of HCPs worldwide.

As the oral cavity remains a largely uncharted territory in the study of COVID-19, HCPs have had to devise strategies to treat COVID tongue, including anti-inflammatory and antiviral medications, chlorhexidine gargles, and antifungals, and management of its symptoms.

Origins of COVID tongue

The term COVID tongue first came into use in 2021 when British professor of genetic epidemiology Tim Spector, MD, tweeted about the prevalence of tongue changes like white patches, erosions, and ulcers among COVID-19 patients.

This information was gleaned from a study published by Zoe Health that began tracking COVID-19 symptoms in March 2020. Soon after, the term became commonly used.^[]

Incidence unknown

A study from 2021 published in Actas Dermo-Sifiliográficas found that up to 11.5% of hospitalized COVID-19 patients exhibited such symptoms.^[]

As more data become available through ongoing global research efforts, the true prevalence of this phenomenon may be better characterized.

Clinical features

Signs and symptoms associated with COVID tongue cited by the Zoe Health report include:

• Tongue swelling (macroglossia)

• Inflammation of the tongue (glossitis)

• Inflammation of lingual papillae (lingual papillitis)

• Tongue pain

• Loss of lingual papillae creating smooth, red, patchy surfaces on the tongue (geographic tongue)^[]

• Aphthous ulcers and cold sores

• Black hairy tongue

• Petechial and hemorrhagic spots

• Loss or alteration of gustatory perception (ageusia and dysgeusia)

• Dryness of tongue

Although prevalent in COVID-19 patients, these symptoms may arise from various etiologies—from viral, bacterial, or fungal infections to poor oral hygiene and the use of antibiotics.

Due to this ambiguity, the CDC does not include tongue lesions in its comprehensive catalog of symptoms associated with COVID-19.

Pathogenesis theories

Some experts believe that the abundance of ACE2 receptors in the tongue may facilitate viral entry and elicit an inflammatory response, as reported in research published by Oral Surgery Oral Medicine Oral Pathology Oral Radiology.^[] The oral cavity—specifically the tongue and oral mucosa—possesses a high density of ACE2 receptors, the key point of entry for the COVID-19 virus.

The virus may target these receptors and cause a cascade of events leading to swelling and inflammation of the tongue and oral mucosa. It also may cause disruptions in the salivary glands, resulting in a dry tongue.

Investigators publishing in Oral and Maxillofacial Surgery proposed that peri-vascular and peri-lymphocytic infiltration, due to overactive immune response, may account for the macroglossia in COVID tongue.^[]

Research published in The American Journal of Surgical Pathology suggested that thrombosis may be the underlying cause.^[] Vessel damage in the tongue triggers thrombotic events. This thrombi-induced vessel damage can lead to vascular lesions and ulcers on the tongue.

Changes in the oral microbial landscape, dry mouth, and prolonged immobility of the tongue in intubated patients are considered potential contributors.

Secondary infection

A more succinct explanation is that the effects of COVID-19—and of the medications used in its treatment—on the immune system may render it more susceptible to secondary fungal and viral infections.

Another such example of secondary infection is the herpes simplex virus type 1-induced cold sores seen over the tongue in COVID-19 patients.

However, these tongue complications may be nothing but a coincidence. Stress and inadequate oral care—which have been prevalent amidst the COVID-19 pandemic—have been shown to aggravate these symptoms.

Symptom management

There is no standard treatment regimen for COVID-19-associated lingual lesions.

Here are some options for addressing various tongue complications:

1. Macroglossia and glossitis are treated with anti-inflammatory or pain-relieving mouth rinse and over-the-counter anti-inflammatory medications. Macroglossia may cause airway obstruction, constituting a medical emergency. This warrants the need for systemic corticosteroids, NSAIDs like aceclofenac and ibuprofen, or immediate decompression therapy.

2. Lingual papillitis and patchy loss of papilla may be caused by candida glossitis. It is treated with antifungal medications like clotrimazole mouth paste and oral antifungals.

3. Tongue pain is managed with non-steroidal anti-inflammatory drugs (NSAIDs), and lignocaine gel or spray.

4. Aphthous ulcers and cold sores are usually self-resolving. Chlorhexidine gargles, povidone-iodine gargles, oral antiviral, and low-level laser therapy might be required in severe cases.

5. Black hairy tongue—or hyperkeratosis—caused by poor oral hygiene, can be treated with good oral hygiene, antifungal medications, chlorhexidine mouthwashes, or topical retinoids.

6. Dry mouth can be alleviated by advising the patient to stay hydrated and avoid caffeinated foods and beverages. Some patients may require artificial saliva.

Understanding of the COVID tongue is based on limited data, and further research is needed to fully unravel the intricacies of this unusual manifestation of the virus, as suggested by the authors of research published in the Journal of Oral Medicine and Oral Surgery.^[]

Nonetheless, HCPs should remain vigilant for this possible symptom, as early detection and management of COVID-19 cases are paramount. Patients who suspect they may have COVID tongue should seek medical attention without delay.