Is it true that having cold sores means you’ve got herpes in your mouth?

--asks Anonymous from Horseshoe Beach, Florida.

September 18, 2006
So much for lipstick! [CREDIT: CDC]
So much for lipstick! [CREDIT: CDC]

Well, yes, that is true. But it’s not necessarily the same herpes that causes problems in one’s nether regions.

Cold sores, or fever blisters, are fluid-filled blisters that appear on or around the lips and sometimes on the nostrils or chin. They’re different from canker sores, which are ulcers that occur in the soft tissue inside the mouth.

The culprit responsible for cold sores is the herpes simplex virus, which comes in two flavors. Garden variety cold sores are usually caused by type 1, while type 2 is commonly the villain behind genital sores. But either strain can lead to sores on the face or on the genitals. Over 85 percent of adults are infected with herpes simplex type 1, although they may not show any symptoms at first exposure.

The herpes simplex virus that causes herpes labialis (that’s the medical name for cold sores) is a sneaky sucker. It infects by entering through skin or mucous-coated surfaces and sets up house in your nerve cells. It’s a latent virus, meaning once it’s infected you, it remains dormant between outbreaks.

The life of a cold sore involves several stages. Warning signs that one is about to raise its blistery head include itching, tingling, and burning. Then the blister appears, starting small and often growing to a bulbous mass. After a few days, the mass breaks and may ooze—this is called the “weeping” stage—after which it scabs over a few times and eventually flakes off to reveal pinkish, healing skin. Generally, cold sores don’t leave scars. On average, lesions last 7-10 days if left untreated.

The bad news is that once you’ve got the cold sore virus, you’re stuck with it. But there are ways to keep it in hibernation longer, and you can also take steps to reduce the amount of time cold sores taint your kisser.

First of all, herpes labialis is most contagious when cold sores are in their weeping stage, so don’t go around sharing utensils, cups, or kisses with someone who has a cold sore. Second, fever, menstruation, stress, and even sun exposure can cause outbreaks, so leading a healthy lifestyle—which includes getting enough sleep and wearing sunscreen—can help.

There are over-the-counter and prescription topical creams and oral medications available that can help reduce the lifespan of a cold sore. Acyclovir is one prescription oral drug that is sometimes used. It works by interfering with viral replication, which happens before a cold sore appears. But viral replication generally occurs before a person shows symptoms, so it’s difficult to judge when acyclovir should be taken. If a cold sore is already present, it may be too late for acyclovir to help, and you’ll just have to ride it out.

Herpes simplex virus type 1 less commonly causes other problems besides cold sores. While it can lead to sores anywhere on the skin, as well as on the eye, in rare cases it can also cause neurological disorders, including encephalitis and Bell’s palsy, a type of facial paralysis. Given these alternatives, a little cold sore doesn’t seem too bad, does it?


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About the Author

BAs in biology/Spanish, from Washington University in St. Louis. Florida-born (ACR, 20+ years!). Love: Hawaii, chocolate, sleep. And also science.



Abby says:

I’ve been getting cold sores for as long as I can remember, but I don’t remember doing anything like kissing to get herpes.

Tonya says:

I may get a cold sore every now and then meaning it can be years. Usually mines come from upset stomach when i eat a lot of junk (processed foods,sweets)and no veggies. For example woke up with one of New Years day! Happy New years to me! But it came from eating a lot of different stuff over the holidays. Basically just going in on whatever i get my hands on cookies candy drinks food etc. Usually to go along with it i have upset stomach and diarrhea But i can get rid of mines in a few days. But it takes constant care. Campho Phenique gel with drying action and my new remedy i researched was apple cider vinegar. The key is to keep it dry as possible. It is uncomfortable but it helps. Do not use vaseline! When it starts to scab then i may use some antibiotic ointment to finish healing.

Lucy cantu says:

I usually flare up after lack of sleep. I really hate how they look and feel. Anything I can do to prevent flare ups?

Deborah Conroy says:

Try LYSINE supplements. I am told that I had cold sores around my mouth when they brought me home from the hospital as a newborn. I had them all through my childhood, in school and as a young adult, which was horrible for a developing psyche. Sun exposure, stress (try getting through high school without stress), acidic food, burns (too-hot pizza cheese, usually) would trigger eruptions. I was getting extreme breakouts several times a year, sometimes mouth, nose and chin at the same time. I have scars on my chin where two large eruptions occurred one right after the other. When I was in my late 20’s a coworker recognized what I was trying to hide with pancake makeup and lipstick. She told me about Lysine supplements. One a day as preventative; three a day when I feel the tell-tale tingle of oncoming breakout, continued throughout the eruption until the healing process begins. It was the best advice I’ve ever received. Cold sores have been rare and manageable ever since I started taking Lysine supplements in the late 80’s. The pills are enormous, but I quickly got used to swallowing them and I never looked back. So far it has remained an inexpensive supplement available wherever vitamins and supplements are sold. (On a humorous note, Michael Crichton used Lysine contingency in his Jurassic Park book as a fail-safe for dinosaur survival outside human supervision. Prior to the movie coming out, very few people had ever heard of the amino acid I was taking on a regular basis.) The reason you get cold sores when eating a lot of junk is that humans cannot make the Lysine amino acid and have to get it externally. Healthy foods (vegetables, soy, etc.) provide the average person with enough of the essential amino acid Lysine to suppress the virus that causes the cold sores.
In addition, the Lysine helps tissue repair, which helps the cold sore heal faster. Campho Phenique hurts like heck when you put it on, but it does help dry up the sore faster. Also ice applied when the first tingle starts can make the eruption smaller. I have actually prevented sores by immediately applying ice and taking a super-dose (three pills) of Lysine.
Good luck! And know that you are far from alone!

Tasha Usher says:

I had four fillings done at the dentist office and the next day my lips were swollen and welts started to appear. Before you know it I had a blisters appear and then I was highly concerned. I thought an allergic reaction to something. I had a follow up appt. to look at this hideous display growing around my mouth and my lips were swollen. I just wanted to cry when the doctor said it looks like herpes ….wth. I never had a cold sore in my life. Now out of nowhere I have this flare up after the dentist. Married 24 years no cold sore by me or him now surprise. I really hope this is a one time thing cause I can’t handle this. Has anyone heard of an outbreak of cold sores after a dentist procedure? Thanks for listening.

Maria says:

After reading this article, I think what I have right now on my lower lip is cold sore. As far I can remember, I never had cold sore until I got my teeth braces April of last year. I thought, it was due to dry lips since I’m not fun of drinking water.

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