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

Julie Leibach

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.

Cameron says:

I’m 15, and I have had cold sores and fever blisters my whole life. They seem to appear when I wake up-like the first thing I feel when I’m awake in my bed is the bump on my lip (sometimes one large bump, and other times a cluster of small bumps). That’s pretty much how it’s always been. I have always tried avoiding kissing my boyfriend for obvious reasons when I have them, and so far, he hasn’t gotten any, when I get them about 1-2 times every 1-2 months. HOWEVER he gets this “facial paralysis” thing (which he has right now and is being helped by his super mom) and now that I just read this article, I’m freaking out, man. Like tfff????? I mean, it IS true that the internet is the worst way to look up your health problems and convince yourself that you’re gonna die, but cmon-DO I HAVE AND STD OR NO??!!

Locust Sprills says:

im gonna help everyone up here when you get one of these things USE RUBBING ALCOHOL it will burn a little but it stops the growth and makes it goes a away really quickly , gone in like a day . stuff like Vaseline, water even feeds it. so just dab some alcohol on there.

Shelly says:

I have a huge cold sore on my lip. I certainly don’t know where it came from as my boyfriend lives in another country so the last time I did any kissing was about 4 months ago when I saw him last. I will admit that I have been eating very badly over the last few months and have been overly stressed, which I read can cause the breakout. It’s been about 3 days and I’m so over walking around with this thing on my lip. I feel like everyone is staring at me and I just want to stay home, locked away until it’s gone.

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.

Patricia says:

I’ve been getting cold sores since I was a baby

Hadio says:

I am so happy today because I am free from herpes virus (HSV2) . I have been having herpes since the past two years now, and I have passed through many different processes in getting rid of the diseases but nothing was working out. A friend of mine introduced me to a doctor (DR JOE ww w. besthealthherbalcentre. co m) who sent me herbal medicines which he prepared for me, and my life got transformed and everything was fine and okay with me. Till now I have been going to check up and it is now going to four months and I am still negative.

Kay Miller says:

I put my lip ring in for an couple of days then as the days go by my lip starts to hurt but he’ll so I took it out after that it start to Iches I didn’t strch it I patted it then I noticed that I was getting an fever blister aka an cold sore is it because my lip ring was to tight and that wat cause the pain and became a cold sore…???…ion understand

yolanda terrell says:

Yes @tasha usher because they were dealing with your mouth alot. For Ex. I had a freaking tiny little blackhead on my lip (everytime i see a pimple i just have to pop it) so of course I’m mashing and squeezing til i got the crap out. So what do you know the next morning i was welcoming a cold sore. Messing round with your lips like that will most definitely bring on a coldsore (i knew that and still did it ). You will now continue to get coldsores so i would advise keeping you some Abreva around and take Lysine supplements to keep it dormant.

Tracy Marper says:

I dont usually get cold sores but after i went dentist’s about 3 weeks ago a couple of days later i had a cold sore, then after a follow up appointment last week i had another outbreak of cold sores the opposite side of my mouth. Im convinced its not coincidence !

Mary says:

Always use llysene when tingle occurs and it will be gone next day .worked for over 25 years for me thank God

Vince says:

Ian unsure of what I have is a cold sore. I thought I was getting a pimple right above my upper lip two days again so I popped it and it sealed normal at the time. The next morning under my mustache I noticed it was all red and almost like a scab. As well as being swollen. I assumed that I squeezed to hard and rubbed the hair from my mustache to hard against my lip while popping the pimple. But it’s been really sore. It didn’t ever seam like a blister though and that’s why I am not sure if this is a cold sore. If anyone knows please let me know. I have never had one before.

Michelle says:

Tasha Usher – this happened to me a few years ago as well! I have never gotten a cold sore before and after I tried a new dentist, I came home and the next day I woke up with 2 bumps on my lower lip. Now I get one once in a while from stress, lack of sleep, or when I catch a cold. I was really worried and upset about it. I feel you!

Andy says:

Thanks for the tips.. I usually do not have cold sore at all but I think I had runny bowel system from food virus.. and all my immune system got flushed. I will try Lysine, funny how it is rarely spoken online about this to prevent cold sores.

Cjdnjsn says:

I have a cold sore and I popped it now I’m going through the swelling stage what can I do to help this virus go away or to help prevent from other people catching it from me

Jackie says:

Going to the dentist makes me blister-prone, maybe it comes from the dentist stretching you lips open so wide, which tears the side of your lips, dang!

N. L says:

Amen on L-Lysine, which I have used with success in reversing some of the few cold sores I’ve had. 1300 mg/day (three 500 mg tabs is close enough) for 4 days. You should see a difference after 2 days. Blessings!

Lisa says:

So very Thankful for all the recommendations on Lysine supplements. I’ve had fever blisters all my adult life, probably starting in my 20’s and I’m now 56.
I was prescribed Valtrex years ago but that doesn’t seem to help me very much. I will definitely get some Lysine supplements as I have 2 fever blisters now…one on each lip on both sides.

Thank you sooo much for this information. I will be going to get these supplements today!

Raven says:

So randomly I had this bump on my lips that wasn’t really a bump but it had some ‘bumbpage’ to it and I haven’t experienced any symptoms relating to herpes. It doesn’t itch and it doesn’t burn or hurt it’s just there. My lips have been really chapped lately so could it be from that?

Sue says:

Ever since I severely sunburned my lips as a teenager, I get cold sores. They come when I eat too much citrus or during stress and weather-related events. Cold and wind are the worst culprits for me. I have found that putting vanilla on it helps to heal it faster, especially if you get to it when you first feel the tingling sensation. Milk also works but vanilla is my preferred method of treating it. I hate cold sores because they do hurt and can be unsightly. But I have been getting them since I was 15 and have learned to live with it.

Martin says:

PLEASE NOTE: When deciding to use “L-Lysine” start with the LOWEST POSSIBLE DOSE and then VERY SLOWLY build if you do not get any relief from your symptoms! L-Lysine worked for me, better than antiviral drugs (I was diagnosed with HSV-1 and HSV-2) but it caused a bizarre rash that was like a sunburn.

My skin became rough and extremely dry! As a black man, I had never had any problems being out in direct sunlight. Suddenly, I was getting this intensely dry, itchy burn that would scrape off when I scratched it and build up under my fingernails!

It took YEARS to get it diagnosed. Hyper-pigmentation! Also known as Melasma and “Mask of Pregnancy”. It was much worse when I was younger, right after I had been using L-Lysine. Once I figured out the L-Lysine was causing the “burn” I stopped using it. I have been using sunblock SPF 50 when I go out and never go out without sunscreen AND lotions on my face, otherwise, I risk dark patches that will not fade without hydroquinone.

Oscar Meza says:

Hi everyone im 41 years old and I’ve been getting cold sores since i was 5 years old i tried just about anything creams liquids home remedies even expensive books herpes be gone for ever , the most expensive products and nothing really works ,only cure there is ,is time except it go through the process and dont stress .

Ann huffman says:

I had a fever blister in my eye and a spot came in my eye. . Went to the eye specialist He treated for years with steroid drops burned the nerve in my eye went partial blind,had the COVID 19, was in hospital when I got home went to do book work notice my eyes seem blurred shut one eye it was find shut my eye with the virus total bind. Never had one two or three fever blister in my life.I Gawker up in the morning and my throat is so dry and my blood pressure is 210/112 soon as I get up will fall 20 points less than 10 minutes then within an hr, it’s 160 thin by lunch time it’s 150 to 135 /70 s . I had a upper/lower gi,mri, and everything find, all drs, says need to change blood pressure medicine I did go to the er or intensive care once. Don’t really think I have blood pressure. Don’t get upset because I have had this a long time and just get up ,it only goes up real high when I sleep and my body stays down until I go to wake up I’m puzzle on what makes it go up. I’m not a dr, but I think if it was my bp it would stay up longer than me waking up

I’m worried says:

I’ve been getting cold sores since I was a child. I’m not sexually active. I’m a virgin. This doesn’t make any sense. So the kids making fun of me in school were right? I do have herpes?

It will get better says:

I got outbreaks really badly at university. It was absolutely horrendous for a while. Lysine didn’t work for me but Aciclovir does. I get mine prescribed by my doctor. You can take 2 or 3 if you feel an outbreak coming or take one every day if you’re going through a stressful time as prevention. Just adding this in case anyone is disappointed that lysine didn’t work for them either. And just remember at least 1 in 4 people have the virus, there’s no shame in it and you’re not alone.

Schwartzman, O'Connell says:

Good lord, there is a lot of confused people here.

For those of you wondering if you have herpes, yes you do. This is simply what it’s called. Cold sores is a nicer sounding version of herpes. And yes, I also have cold sores / herpes.

I got the virus from my mother, I think I was getting cold sores before I was 10 years old.
My sister never got a cold sore. Doesn’t mean she doesn’t carry the virus, just means it doesn’t flare up in her.
My father also never had a flare-up and surely he spent enough time with my mother to get the virus too.
A LOT of people carry the virus, they just never have a flare up.

I am 37-years-old now and my outbreaks are becoming less and less frequent.
Living a healthy lifestyles, stress-free, not smoking, staying out of extreme weather (heat and cold) and protecting my lips from the elements helps me not have a flare up.

Lysine is a big help, take a supplement every day. Stay hydrated and look after your skin…..

If you’re waking up at night with a bump or a tingle, here is my advice.

– ICE IT! IMMEDIATELY! FOR 20-30min or as long as you can stand.
Take a break for 20-30min, then ICE IT! AGAIN! It stops the flare up in it’s tracks and helps with swelling.

– After icing (best if you have a day off work or work from home), suss out what it’s going to do, if you’ve caught it quick enough it will never eventuate and you can put some soothing peppermint / carmex on it and hope it doesn’t split.


If it’s already started to bubble you can tackle it in two ways,

– Open it up. So this is where alcohol or tea tree comes in…. It’s going to dry it out super quick but most of the time you will be left with a bleeding sore but it won’t grow bigger….. and it’s the quicker way of healing it. I do this when I have a few days of not having to go anywhere and I can really concentrate on healing it quickly… So I basically dab a cotton ball with tea tree and hold it against the bubbles, sometimes I will prick the bubbles with a pin so it can get in there and dry it out. Then I clean it up, put a healing ointment (tea tree, paw paw) and put a band aid (plaster) over it. I sleep with the plaster over my lip at night so it doesn’t get scabby, split. So I technically keep the scab moist, so it eventually falls away and I am left with a red mark, instead of it drying out / keep bleeding (takes longer to heal).

– The other option is to just deal with whatever it decides it wants to do after icing it for as long as possible. You can get lucky and it can heal / go away very quickly. This is when I used Zovirax (or equiv) sparingly for maybe a day, until I feel it’s dried it out. Then, at night, I will mix zovirax with paw paw or a tea tree ointment, so it’s still working to kill the outbreak but it’s not going to completely dry it out / open up the wound. This is a delicate balance and it’s time consuming, so it’s harder to do if you don’t spend most of your time at home.

I must say. It sucks having cold sores. The stigma, the way people look at you etc. I have a fair few friends who get them but you still feel like you’re the only one.

Good luck!

Dave says:

Hi, I am Dave. I run a site selling at home herpes test kits. If you can allow this and help empower others to know their sexual health from the privacy of their own home, that would be great. Thanks.

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