Is a canker sore and a cold sore the same

These two mouth irritants aren’t the same thing. Find out how to tell which one you might have and, better yet, what to do about them.

Although sores in and around the mouth may be embarrassing, they shouldn’t be, because they’re very common. At least half the population gets canker sores, and about the same amount gets the virus that can cause cold sores. But the two types of sores are completely different, so here’s what you need to know to tell them apart.

1. Known versus unknown causes

Cold sores, also called fever blisters or oral herpes, are most often caused by the herpes simplex virus type 1, which people usually pick up in childhood. Although the virus then settles into bundles of nerve cells in the body and may never bother you again, it stays with you for the rest of your life and can pop up from time to time.

The causes of canker sores, or aphthous ulcers, are less known. It may be that the immune system mistakenly attacks the mucous cells of the mouth. Canker sores are also linked to Crohn’s disease and other systemic conditions, including nutritional deficiencies; they may also be caused by stress, hormonal shifts or allergic reactions to certain ingredients in food or toothpaste.

2. Oozing blister outside the mouth versus painful ulcer inside

The way cold sores and canker sores appear is very different, too. Cold sores occur most often outside your mouth, in the corners or on your lip. If you find one inside, it’s usually on harder tissue, such as your gums or the roof of your mouth. Cold sores form blisters that then break open, ooze and crust over. You may feel a tingling or burning sensation before a blister appears.

Canker sores are small and round or oval and develop in the soft tissue inside your mouth. You might get one behind your lip, on the inside of your cheek or under your tongue. They’re red, flat and often have a whitish top. If they become large or painful, they may prevent you from comfortably eating and drinking.

3. Contagious versus not contagious

Perhaps the most important thing to know is whether these conditions can be passed to others. Cold sores are highly contagious, especially when you have an active one — but you can transmit the virus even when you don’t. It’s spread by saliva or skin contact. If you touch your cold sore, wash your hands right away to avoid spreading the virus to other parts of your skin.

Canker sores, on the other hand, aren’t contagious, so you don’t have to worry about giving them to anyone else.

If they do show up, what’s the best treatment?

Most of the time, both types of sores will heal by themselves within a week or two, but medications are available to ease their effects.

For cold sores, taking an antiviral medication at the earliest sign may reduce pain and shorten the outbreak, according to Sharon Orrange, MD, an internal medicine physician at Keck Medicine of USC and clinical associate professor of medicine at the Keck School of Medicine of USC. The type of medication you choose, however, can have an impact.

“Topical medications for cold sores don’t work that well, are expensive and usually require frequent daily applications,” Dr. Orrange says. “But evidence shows that drugs such as valacyclovir effectively reduce both healing time and the duration of pain.”

For small, painful canker sores, she suggests using an over-the-counter numbing medication. But if you have large painful canker sores that are making it difficult to eat, you should ask your physician for help.

“Prescription pastes and gels are available that can help speed your healing,” Orrange says. “Also, see your doctor if your canker sores recur, because the recurrence could indicate celiac disease, inflammatory bowel disease or HIV.”

Although they’re annoying, sometimes painful and can’t be cured, there’s good news about canker and cold sores: In the majority of cases, both are relatively harmless and don’t have lasting consequences.

Topics

canker sores

celiac disease

cold sores

Crohn’s disease

Dr. Sharon Orrange

Tina Donvito is a freelance writer covering health, culture, travel and parenting.

At our office, we know many people have experienced some form of mouth sores or irritation. Some mouth sores are harmless and go away on their own after a few days, while others are more serious and should not be ignored. Mouth sores occur for many different reasons, but bacterial infections, viruses, or funguses often trigger them. The best way to tell the difference between a canker sore and a cold sore is that canker sores occur inside the mouth while cold sores occur on the outside the mouth.

The most common mouth sores are:

Canker sores: A non-contagious, small, grayish ulcer with a red border, canker sores appear inside the mouth. While outside factors such as stress, fatigue, or allergies may increase the chances of developing a canker sore, most health experts believe they stem from bacteria or a virus that attacks the immune system. Canker sores typically heal within a week or two.

Cold sores: Also called fever blisters, cold sores are contagious groups of fluid-filled blisters that often erupt around the lips and sometimes under the nose or around the chin. Cold sores are the result of the herpes simplex virus, and once infected, the virus remains in the person’s blood stream.

Leukoplakia: A potential warning sign of oral cancer, leukoplakia is a premalignant lesion that appears as a white patch on the inside of the mouth, tongue, or gums. The lesions, which are caused by excessive cell growth, usually afflict those who smoke tobacco. Dr. Craig S. Donn may choose to have the lesion biopsied if the outbreak appears severe.

Oral candidiasis: Also called oral thrush or moniliasis, this condition is caused by the overgrowth of a type of yeast called candida. Common symptoms of oral candidiasis include white spots inside the mouth and on the tongue, redness or discomfort in the mouth area, sore throat,difficulty swallowing, and cracking at the corners of the mouth. It is important to visit Dr. Craig S. Donn if you have oral candidiasis. If left untreated, it may infect your bloodstream, which can be very dangerous. Healthy adults do not usually get thrush, and the condition is most often seen in infants, the elderly, patients undergoing chemotherapy, or people with AIDS or other diseases that are known to weaken the immune system.

Should you have a mouth sore that lasts a week or longer, we encourage you to give us a call and schedule an examination at our Cherry Hill, NJ office.

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