What is the Connection Between Canker Sores and Herpes?

Herpes lesions that present inside the mouth, known as cold sores, can be mistaken for a canker sore, or aphthous ulcer. Canker sores and herpes lesions are both open sores, however, their presentation and how and where the sores form are very different. Treatment for canker sores and herpes lesions can both involve the administration of topical and oral medications to reduce inflammation and aid with the healing process.

Canker sores are oftentimes mistaken for cold sores, which are caused by the contagious herpes simplex virus. There is no known, definitive cause for the development of canker sores. Minor outbreaks of canker sores and herpes cold sores generally do not necessitate treatment. Persistent outbreaks of canker sores and herpes that are moderate to severe in presentation can require the use of topical and oral medications to speed the healing process.

Outbreaks of canker sores and herpes can be triggered by a variety of factors. Most outbreaks last a few days, but more severe presentations can last up to a couple of weeks. Individuals with hypersensitive or compromised immunity, food allergies, or high stress often experience frequent canker sore development. The herpes simplex virus remains dormant in the systems of those who have been exposed. During times of extreme stress or fatigue, menstruation, or illness, the virus can reactivate, causing infectious cold sore formation outside or inside the oral cavity.

Most canker sore and herpes cold sore development is heralded by a tingling sensation that presents a few days before the lesion forms. A single herpes lesion will develop from several blister-like sores and adopt a jagged border that forms on hard tissues, such as the gums or upper palate. Cold sores can cause significant discomfort and impair one’s ability to eat, drink, and, sometimes, speak clearly. The sore will fill with ooze, rupture and crust over usually without scarring. An aphthous ulcer, or canker sore, initially presents as an inflamed raised area, similar to a pimple, before forming an open sore on the soft tissues within the mouth, such as the tongue or cheek.

Minor canker sores are usually oval-shaped, yellow or white in color, and will heal without scarring. Moderate to severe sore development can adopt an asymmetrical shape and scar. As individuals age, canker sore outbreaks can become herpetic in presentation, such as cluster outbreaks of multiple sores. It is not uncommon for severe or herpetic outbreaks to trigger additional symptoms similar to those experienced with a herpes cold sore outbreak, including fever and malaise. Persistent or severe canker sore outbreaks or sores that last for several weeks can be indicative of a more serious medical condition necessitating a biopsy of the affected area.

Moderate to severe outbreaks of canker sores and herpes cold sores will usually necessitate the use of a topical medication to alleviate discomfort and help speed the healing process. Usually, over-the-counter topical ointments are recommended for moderate outbreaks. In some cases, a physician may prescribe an oral rinse or medication that is steroidal-based to reduce inflammation if an individual is unresponsive to traditional treatments. When an existing condition contributes to canker sore and herpes cold sore development, such as compromised immunity, nutritional and dietary supplements may be recommended to boost the body’s defenses and help prevent future outbreaks.