While fever, cough, and fatigue are recognized signs of COVID-19, the virus can also present with other symptoms. Among these are oral health issues, including different types of mouth sores and discomfort. For some individuals, these oral manifestations can be an early indicator of infection or can develop during the illness.
Common Oral Symptoms Linked to COVID-19
One of the more frequently reported oral issues with a COVID-19 infection is the appearance of ulcers that resemble common canker sores, known as aphthous-like lesions. These can be painful, round, or irregularly shaped sores that develop on the tongue, lips, palate, or inner cheeks. They may appear as single ulcers or in clusters, causing discomfort when eating and speaking.
Beyond ulcers, some people experience generalized inflammation and redness inside the mouth (stomatitis). Another symptom is “COVID tongue,” which can encompass a swollen tongue (glossitis), white patches, or a “geographic tongue” pattern. These symptoms are often accompanied by other oral complaints, such as dry mouth (xerostomia) and an altered or complete loss of taste.
Dry mouth can make it difficult to swallow, while changes in taste and smell are also well-documented. These oral issues can appear at different times, sometimes showing up two days before other COVID-19 symptoms or as late as three weeks after.
Why COVID-19 May Cause Mouth Sores
The development of mouth sores during a COVID-19 infection is multifactorial. One theory points to the body’s intense inflammatory response to the virus. This systemic inflammation, sometimes called a cytokine storm, can disrupt the sensitive mucosal tissues inside the mouth, leading to lesions like aphthous ulcers.
Another explanation is the direct action of the SARS-CoV-2 virus on oral cells. Cells in the oral cavity, particularly on the tongue and in salivary glands, have a high concentration of angiotensin-converting enzyme 2 (ACE2) receptors. The virus uses these receptors to enter and infect cells, triggering localized inflammation and tissue damage. This direct viral activity may also explain dry mouth and taste loss, as the salivary glands and taste buds are affected.
A weakened immune system is another factor. As the body fights the primary viral infection, it can become more susceptible to secondary infections. This can allow for the overgrowth of fungi or the reactivation of dormant viruses. For example, some patients develop oral thrush (candidiasis), a fungal infection with white patches, or experience a flare-up of the herpes simplex virus.
At-Home Care for Oral Discomfort
Managing the discomfort of mouth sores at home focuses on soothing the irritation. A simple measure is to modify your diet by avoiding spicy, salty, or acidic foods and drinks that can cause stinging pain. Opting for softer, blander foods can make eating more comfortable until the lesions heal.
Gentle but consistent oral hygiene is also helpful. Using a toothbrush with soft bristles can prevent further irritation to sensitive gums and sores. Rinsing your mouth several times a day with a warm saltwater solution can help cleanse the area and reduce inflammation. Avoid mouthwashes that contain alcohol, as they can cause a burning sensation and dry out the mouth.
For targeted relief, over-the-counter products can be beneficial. Topical anesthetic gels can numb the area, providing temporary pain relief, while medicated oral rinses may also help manage symptoms. Sucking on ice chips or sugar-free candy can help keep the mouth moist, which is useful for those experiencing dry mouth.
When to Consult a Doctor or Dentist
While many mouth sores related to COVID-19 resolve on their own, consult a healthcare provider if the sores persist for more than two or three weeks without improving. Sores that are unusually large, located near the back of the throat, or interfere with your ability to swallow also require evaluation. You should also seek professional advice if the pain is severe and not managed with over-the-counter remedies, or if sores are spreading, worsening, or accompanied by a high fever.
The appearance of certain lesions should also prompt a consultation. For instance, thick, white patches on the tongue or inner cheeks may signal a fungal infection like oral thrush, which requires prescription medication. Similarly, any sores that bleed easily or are unusually red and painful might be a sign of a secondary infection needing medical intervention.