What Is the Difference Between a Cold Sore and a Canker Sore?

What Is the Difference Between a Cold Sore and a Canker Sore?

Some use the terms “cold sore” and “canker sore” interchangeably, but they are not the same. While both are pesky and painful mouth sores and seem to appear spontaneously, this is where the similarities between the two end.

What Are Cold Sores?

Cold sores, also called fever blisters or the herpes simplex virus I (HSV-1), are a viral infection. Infections generally appear outside the mouth or on the lips, and rarely on the cheeks or nose. Very rarely, they appear in the eye. HSV-1 is incredibly common, and nearly 90% of adults are infected with the virus but never experience symptoms. Symptoms of the initial infection are similar to other viral infections: fever, swollen glands, and fatigue, in addition to sores in the mouth and/or the gums. The sores generally appear clear at first and then turn cloudy, and pus-filled. They dry up, crust, and heal usually within a week to 10 days. Most people have less severe recurrences than their first infection.

The herpes simplex virus (HSV) has two types and they are typically differentiated by location; however, it is possible to have HSV-1 or HSV-2 either above or below the waist. HSV-1 generally occurs above the waist, while HSV-2 is usually below the waist. HSV-2, or genital herpes, is most commonly transmitted through sexual contact, and sores appear in the genital area.

Can I Get Genital Herpes from Oral Cold Sores?

Yes. HSV-1 and HSV-2 are both highly contagious, and you may transmit sores by any contact until sores are healed. That means even oral sex can transmit herpes to your partner’s genitals. Many people with HSV can even transmit the virus when they have no sores. Therefore, if you are sexually-active, you should use condom or latex barriers during every oral sexual encounter if you have HSV-1.

However, it is almost impossible to transmit your own HSV-1 infection to your genitals, say, by using the same towel in both areas.

Should I See a Doctor for Cold Sores?

While there is no cure for any virus, including HSV-1, the sores can be treated and managed. You should seek medical care if your cold sores drain pus and/or they do not go away after 10 days. If you develop a high fever, see a doctor.

What Are Canker Sores?

Canker sores, also called aphthous ulcers, are not a virus and not contagious, unlike cold sores. Symptoms of canker sores include painful open sores which appear grey or white and are surrounded with a red inflamed area. They only occur inside the mouth. They usually are painful and uncomfortable for 3-4 days, but completely heal within 15 days. Most are harmless, long-term, unless you have an underlying immune system dysfunction.

There is no identifiable cause of canker sores, only several known triggers. Many people who suffer from canker sores get them frequently, as they can be caused by eating citrus or other acidic foods. Unfortunately, there is no cure or way to prevent canker sores. There are ways to relieve discomfort, though, such as applying a topical gel such as benzocaine to numb the sore. When you have a sore, avoid abrasive or spicy foods and try not to irritate any sores while brushing your teeth. You may be able to prevent infection and promote healing of canker sores by using cleansing antiseptic medications or rinses, many of which are available at any drug store without a prescription.

If you experience frequent canker sores, you should be tested for allergies and avoid eating certain foods to minimize the risk of canker sores due to food allergies.

Concerned about a pesky mouth sore and still wondering whether it’s a canker sore or a cold sore? Come to Primary Care Associates of Texas for an appointment. You can book your consultation online or call us at .


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