Is a cold sore and canker sore the same

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.

A little irritation develops near or inside your mouth, and you start to wonder what’s wrong. It hurts a lot more than it should, considering the small size. It seems to last awhile, and you can’t figure out whether it’s a cold sore or canker sore.

So, what exactly is the difference between a cold sore and a canker sore? Let’s dive in. Fortunately, it’s not too complicated.

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Cold Sore vs. Canker Sore

The location of the sore can often help you identify if it’s a canker sore or a cold sore. Cold sores often appear around the lips and the outside of the mouth, whereas canker sores only occur within the mouth.

What Is a Cold Sore?

Outside of the mouth is where you’ll find a cold sore, sometimes called a fever blister. It usually appears as one or several red, blistered areas on your lips. The blisters often will break open causing an open sore, or ulcer.

Within a few days, a scab will form. Some areas of the mouth take longer to heal because they frequently stretch when you talk, eat, or yawn.

Symptoms depend if you have a new infection of herpes simplex virus (HSV), which causes the sores, or if you’ve had the virus for a while. If you have a new infection, your symptoms may include:

• Burning or tingling and the development of sores on and around the lips and mouth
• Fever
• Headache
• Sore throat or pain when swallowing
• Swollen lymph nodes
• Nausea

If you have had HSV for a while, you may experience cold sores periodically. Early symptoms may include burning, itching, or stinging around the mouth prior to the sores forming.

What Causes Cold Sores?

What causes cold sores is HSV and, unfortunately, the sores are contagious when they’re open. The virus can be spread through the following:

• Sharing utensils, drinks, towels
• Close person-to-person contact such as kissing
• Using someone else’s lip balm or lipstick

The herpes virus stays in your body and can cause cold sore outbreaks at any time. Often, they’re triggered by things such as extreme temperatures, exhaustion, stress, or a weakened immune system.

When you feel a cold sore coming on, usually indicated by a tingling or itching on the affected area, consider anything out of the ordinary that you’ve been experiencing, as this could be your trigger. Once you figure out what your triggers are, you can try to avoid them. Use sunblock if a cold sore is caused by sun exposure or take a few minutes to relax if stress is a trigger for you.

How to Treat a Cold Sore

While there’s no cure for cold sores, treatment can help to shorten the lifespan or weaken the severity. Some people start treatment when they first notice symptoms. A cold sore treatment is for symptom relief, and can include:

• Antiviral topical ointment
• Oral antiviral medication
• Over-the-counter topical anesthetic or anti-inflammation agents

Your first cold sore can take up to three weeks to heal, but later ones may disappear in a week or two. While there’s not usually a reason to go to the doctor for a cold sore, your doctor can test for the virus with a swab and culture and prescribe antiviral medication.

What Are Canker Sores?

Canker sores are found on the inside of the mouth, including the lips, cheeks, and tongue. They’re small ulcers that usually have a red base and may be covered by a white or yellow layer. Common symptoms include:

• Bleeding gums
• Painful gums
• A painful lump on the gums

What Causes Canker Sores?

Canker sores can be caused by things such as:

• Food allergies
• A weakened immune system
• Stress
• Mouth injury (like biting your tongue or cheek)
• Some medicines
• Viruses/bacteria
• Irritation caused by orthodontic braces

How to Treat Canker Sores

Canker sores aren’t contagious, and they are not easily visible to others. They can be painful, though.

• Try an oral pain reliever since ointments are difficult to keep in place when the sore is inside your mouth.
• Keep your mouth clean by brushing regularly
• Use an anesthetic mouth rinse to ease pain
• Avoid spicy, acidic, or salty foods during healing, which can take up to two weeks

There’s no reason to go to the doctor unless the sores return frequently or are large.

So, what is the difference between canker sore versus cold sore? Location, location, location! Cold sores are usually on the edge of the lips, while canker sores are inside the mouth. Cold sores are contagious and can be treated with antiviral ointments and pain relievers, while canker sores require only pain relief. And both can last a few weeks.

For more information on treating oral sores or to find a doctor, contact UPMC.

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