cold sores

Q. I have always suffered from terrible cold sores as far back as I can remember. I am especially vulnerable in the summer when I spend a lot of time outdoors. Even with lip balm that has a sunblock I am frequently in pain.

These sores are incredibly ugly and people always stare. That makes me even more self-conscious about them. What can you recommend to prevent cold sores or speed healing once they occur? I have heard that lysine might be good but I know nothing about this stuff. What is it and how well does it work?

A. Cold sores, also called fever blisters, can be painful and look yucky. Some people have outbreaks once or twice a year. Others seem to have recurrent lesions every few weeks. Once our bodies are infected with this herpes virus it remains forever. Why some people are more vulnerable to attacks than others remains mysterious. Clearly our immune systems play an important role in this process. Sun exposure can bring on an outbreak. So can a trip to the dentist (presumably because of mild trauma associated with such procedures).

Although we are enthusiastic about lysine (more about this supplement in a minute) we would be remiss if we did not mention that there are effective anti-viral agents for type 1 (HSV-1) herpes infections that cause cold sores. Zovirax (acyclovir) and Denavir (penciclovir) are available in cream form. Your doctor could alsp prescribe oral anti-virals as Famvir (famciclovir), Valtrex (valacyclovir), and Zovirax.

If you prefer a more natural and affordable approach, you may want to seriously consider lysine. The arginine/lysine theory of cold sore management remains somewhat controversial within the medical community. It goes something like this. The amino acid arginine is essential for herpes viruses to replicate and multiply. Arginine is high in nuts (such as almonds, Brazil nuts, peanuts, walnuts, etc), pumpkin and squash seeds, sesame seeds, red meat and some cereals (oatmeal for example). People are advised to cut back on high arginine-containing foods and add lysine supplements to their regimen (1000 to 1500 mg total daily dose). Lysine is supposed to make it harder for the herpes virus to replicate.

We were somewhat skeptical of this approach as there were been both negative as well as positive studies with lysine. Most of the research was with small numbers of patients and seemed inconclusive to us. Nevertheless, some of the double-blind, placebo-controlled trials lasted from 12 to 52 weeks and reported significant reductions in cold sore outbreaks among the lysine groups.

What has convinced us that something positive was happening with lysine has been the outpouring of letters from dental professionals and our readers. We have received so many anecdotal reports of success that we are convinced something is going on here We share just some of the lysine success stories with you:

One oral surgeon wrote to say his patients do well on a preventive regimen of one 500 mg tablet of l-lysine daily. If they develop a sore, increasing to four tablets a day seems to help it heal faster. A reader said, “I suffered from cold sores since I was a little boy and my doctor prescribed acyclovir, which wasn’t any help. My pharmacist suggested lysine, and I have been taking 500 mg of this amino acid for two years now. I am free of fever blisters and that’s a great relief.”

Q. When you wrote recently about home remedies for cold sores, why in heavens name didn’t you tell peple about l-lysine?

For 50 years I would develop fever blisters every time I went out in the sun. About 4 years ago a pharmacist told me about l-lysine. Since then I have taken it for a week before I know I’ll be exposed to sunshine. I have not had a cold sore since.

A. We were flooded with letters like yours praising the power of l-lysine. One young woman writes, “my boyfriend got these sores constantly, and as a last resort we went to the health food store to see if there was anything that could help. He was told to take lysine and the sores have never returned.”

Another reader reports suffering from nasty fever blisters that lasted 3 or 4 weeks. She was told by a friend to take lysine, and when she was skeptical the friend said, “then live with them if you’re stubborn.”

She now takes l-lysine whenever she feels a cold sore coming on or if she is in the sun more than usual. She says, “it quickly nips them in the bud. Doctors and druggists don’t seem to believe this, but I know it works.”

Judging from our mail bag, l-lysine does help many people. Though it may not work for everyone, this amino acid may be worth a try.

We would love to hear your story (positive or negative). Share your experience with l-lysine below in the comment section.

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  1. Rocky

    Vitamin B12 causes cold sores for me, have to avoid it.

  2. Bobbi

    When I feel that tale-tale tingling that almost always comes just prior to the cold sore I immediately begin taking L-lysine in megadoses, I also apply Campho Phenique gel many, many times a day which drys the lips, so I follow those applications with Carmex. Since I began this regimen, I rarely get them.
    btw – if my lips get very chapped, a cold sore usually follows, or tries to!

  3. Les Green
    Atlanta, GA

    Nothing works..believe me. When I catch a virus or a cold, i get huge cold sores all over my face…multiple ones too. I have tried everything and nothing has worked.

  4. Kay
    Napa, CA

    I’d like to add something bizarre. Ha. So… I’ve had cold sores since I can remember. I’m 29. And I get them multiple times a year, religiously. However, I thought it was interesting that during my pregnancy, and the 2 years after that I breastfed, I did not get ONE outbreak. Once I stopped breastfeeding, they began to return in the usual frequency. I’m curious if it was related to my hormones/immunity.

  5. Kay
    Napa, CA

    I use L-lysine the second I can tell one is coming, and it doesn’t seem to help with me. I still use it, though. Ha. Hoping to ask for an anti-viral oral medication soon. I seem to hear that those work well. None of the over the counter topicals ever work for me. But, again, I still use them. So who knows, maybe they lessen my symptoms.

  6. Ruby

    I started suffering from them as a little child and I think it was due to the big sloppy kisses my mother and grandma used to give me even when they had cold sores. I do wish people wouldn’t kiss children on the lips as they do not know if they are carriers or not. For some reason I hadn’t had an outbreak for 5 years then last year whilst on holiday in the sun I didn’t protect myself properly on the first day and got 2 on my lips, I had to bear these unsightly things for my holiday and yes people are rude enough to stare, if I had known I would have taken a bell and rang it and shouted clear the beach the infected monster is here.

    Anyway, I had no more until the past month then 2 and now another 2 and what did I do to deserve them? eat nuts! Thanks to all the people on the internet that bought my attention to that, otherwise I would have never known that they were the cause. I will look into the cold sore machine from Boots chemist it is said to be very effective and as a five year guarantee if its prescribed by your GP.

  7. Andy

    You guys all need to look up the electronic cold sore healing machine. It is sold here in Boots in the UK.

    If I feel a cold sore coming on, I zap it with the machine, and 70% of the time it won’t appear. If it does appear, they only last a few days if I use the machine, and don’t leave me with the yucky feeling.

  8. sally

    I have had these aggravating cold sores or fever blisers for years. Yes, I did have chicken pox as a child and I understand this makes you vulnerable. Once, I had one that would not go away and I do believe it got infected. It lasted a month and I was extremely depressed, couldn’t go anywhere. Never had one that bad since.

    A friend told me to get Llisine and never forget to take it. Everytime I do forget or go out in the sun, I’m sure to get one! Anyone recomment a good sun block for lips or the fever blisters, bring it on! I hate these things!

  9. Aindreas Scholz

    I have been suffering from recurrent cold sores for the past 10 years. Over the years, I have tried many things to either prevent or minimise the symptoms. Personally speaking, I found Acyclovir 200mg capsules to be very effective. In fact, since taking the capsules I experience less and less cold sore attacks per year. In addition, I noticed that electric dry shaving increases my chances of developing cold sores. I now only wet shave. Hope this helps. Andreas

  10. Coco

    Lysine is the only thing that can stop a coldsore for me. I start taking it every 4 hours once I feel one. Never thought to continually take it but now I may add it to my daily vitamin regimen!

  11. Carole
    New Jersey

    What lysine brand do you recommend??

  12. Megan

    I am desperate for recommendations or if anyone suffers from cold sores as badly as I do. This fall i started getting them on and around my mouth. I started taking valtrex and went without one for about a month. However, Since November I have literally suffered with a cold sore EVERY WEEK. I have tried 4 different anti-virals in pill form, zovirax cream, abreva, campho, and when all of those stopped working I started taking 1000 mg of lysine 3 times a day but I am still suffering. It is a mystery. My doctor said I likely have a compromised immune system as she and my dermatologist have never heard of anything like it..I try taking vitamins, milk, but nothing is stopping these awful things. Not only are they embarrassing but painful! If anyone has any sort of idea or recommendation please let me know.

    • TARA

      I am with everyone on this board. I have been suffering with fever blisters(herpes 1 virus) my whole life. I am 42 year old female. I have shingles (herpes 3 virus) 1 month now they are going away but very very slow. Now I just woke up today and have fever blisters under my nose. This is where I usually get them every time on right side and the right side of my neck gland swells. My lymph node swelled under my armpit on left side where I have these shingles. Take lysine everyday. Watch what I eat nuts,chocolate,grains etc.. I get stressed easily and I know this contributes to these fever/shingles virus! I hate the fact there is nothing that can be done to rid these forever? The prescribed valcyclovir pills & denavir creams just don’t work for me. I have started taking oil of oregano and using that on the blisters it’s an antiviral & antibacterial supplement. I am just at my wits end. It seems I am riddled with this virus inside me? It’s just so frustrating

    • BPC

      Have you found something that has worked for you? I am in the exact same scenerio. I have had them my whole life but it was usually just 1-2 times a year. Now it is more like once a week. Even started taking valtrex once an day and still got them.

    • Kylie

      Hi Megan, I know you seem to be getting these more regularly than every month, but please make sure that you try to avoid any medication containing naproxen, which is used in some period pain medicines . I can’t explain explain the link but I used to experience terrible coldsores every month and eventually found that for some reason the naprogesic I was taking was triggering attacks. I stopped taking it and didn’t have a cold sore for more than 15 years. It may not be of any help but, just in case I thought best to share this

    • Ruby

      If you eat nuts you should give them up for a couple of weeks and see if it helps.

  13. angel

    I have been getting cold sores irregularly since I was infected about 7 years ago. In the last 2 and a half years I’ve had less than five outbreaks except the last week I’ve had 6 cold sores. I am attributing this to taking olive leaf extract (it destroys viruses within the body and temporarily worsens symptoms) so my body is working over time.

    Triggers for me include extreme stress and being run down/ill although I had a recent infection and never got a cold sore. My daily regime is: 1000mg vitamin c and zinc, copper, vitamin b and 1000mg l-lysine, an olive leaf in the morning then another one in the evening with my meal then a garlic oil before bed. I sometimes take reishi mushroom extract too 1 a day just during my current outbreak.

    I also follow a relatively balance/low arginine diet and balance meals, however these last few weeks I’ve crept up to 3 coffees a day from my usual 2 which seems to have had an impact and triggered my cold sores. I treat with sudacrem (zinc oxide) and lysine ointment works a charm. My 6 cold sores never came up and blistered just remained flat and are almost healed (2 at the start of the previous week that quickly went and the last 4 about 36 hours of having them so far)

  14. Jessica L
    Marianna FL

    I had 1 fever blister when I was 15 after getting a sunburn on my face and apparently my lips, 1 fever blister at age 24. Now I’m 36 and in the last 2 years I have started getting them regularly. It started every couple months and now every month.

    I read on another site to try Lysine and it said to take 1000 mg every 6 hrs during an outbreak. It said it only takes 5 hours for the pill to go from your stomach to your lip tissue to stop the replication of the virus and it was right. I found that article at 8am with a small cluster of new blisters and by the next morning it was completely flat and didn’t hurt, on the 2nd day it was completely gone.

    It was about 32 hrs from the first sign to gone, it had erased it completely. I went from the 4 pills a day to 3 pills a day and then 2, 1000mg pills a day within 4 days of starting. Now this morning I awoke to a new cluster on a different place on my lip.

    My new strategy is to start the 4 pills a day and keep taking the 4 pills for a full week this time before weening down to 3 and then 2 and then hopefully some day just one a day. If anyone else first this be aware that one site said large doses for long periods (they said long periods being 5 years) can cause kidney inflammation and to cut back on dairy because lysine can make you absorb too much and cause gallstones. I don’t know if it’s true just thought I would mention it so if you try this and all of a sudden get kidney pain or discomfort you can stop taking it.

    I will say that the only thing I have changed since starting to get fever blisters often is I started DRINKING COFFEE. I never made the connection until reading this thread. All of the other triggers that were mentioned I don’t believe trigger mine because I gave not increased the eating of nuts or chocolate BUT coffee I started drinking lots more of after I had my son because having a baby is exhausting. I will stop drinking coffee and see what happens.

    • Dori

      Vitamin C will give me a cold sore. For some reason if I take 1000mg of C I get a cold sore. So try taking less vit C to see if it will help. I just do not take vitamin C.

  15. Laura

    Milk. Something about the amino acids or proteins. No chocolate or peanuts (I still eat other nuts and it doesnt seem to make the outbreak worse). Lots of milk and lysine. And milk.

  16. Valerie

    This virus is highly contagious, be very careful not to spread it to the rest of your body, especially into your eyes. I got infected 8 months ago by taking a sip from my friend’s bottle at a summer festival. We both forgot she had a small cold sore on her lip when she passed me her cider. I developed a cold sore almost the next day and the virus has been torturing me ever since. I’m 29, healthy and athletic, with a pretty strong immune system, I used to think. From having 4 outbreaks in the past 8 months, I’ve learned my triggers are stress, menstruation, and alcohol.

    After the first two outbreaks, one right after the other, I started taking Trilex supplement from Natural Wellbeing with lysine (+other natural extracts) and it worked!! I didn’t have another outbreak in 5 months until I decided to take a break from lysine. Going through my second cold sore this month, I’ve realized I absolutely have to:
    -take lysine for the next few months
    -alternate it with elderberry extract
    -start coconut oil pulling
    -try immediate icing at the first signs of a cold sore (it seems to work for many people)

    It could be just me, but Abreva or acyclovir cream do not help at all.
    To speed up healing this new cream Aubio works for me, it’s a little overpriced though. After applying it every 2 hours to a freshly developed cold sore, I have a brown scab the next day. Then I apply tea tree oil so that the scab dries out and falls off over the next couple of days.

    Before using Aubio, my healing period was 7-10 days, which is now cut in half. Hopefully, the right diet (NO coffee, almond milk, nuts, and seeds), lysine and elderberry supplements, oil pulling, and vitamin C will keep me cold sore-free. It’s also very important to relax, and try not to stress out. Good luck to all of us!

    • Jay

      I got cold sores from sharing drink question is how you maintain daily hygiene and routine..thanks for any comment

  17. Lora

    I have gotten cold sores since I was a child…am now 40 and getting the a lot…I never knew that nuts could contribute! I have been eating tons of nuts lately…that might be the reason. It’s a bummer to stop eating them, but I will try and am going to add lysine.

  18. Lynn

    I am 66 and am getting a cold sore about every couple of months.I use to get one once or twice a year.
    I thought cold sores lessened as you got older.Any answers as to why it has increased for me? I am a very healthy woman, but wondering it could be a suppressed immune system.

  19. Little Lumatic
    Victoria BC

    I get terrible fever blisters every 4 months, about 3 or 4 at a time. It’s awful! I work in dental too, so my patients often give me weird looks. Maybe I’ll try the I Iysine thing. I’ll try Anything at this point.

  20. Sam

    Nothing has really worked for me either. This year has been the worst year for me. I actually did a lot of detoxifying treatments such as iodized foot baths and 2 colonics and I got outbreaks right after treatments. My guess was that my body was doing just that…detoxifying…but, unfortunately in the form of herpes. I’ve been getting them since early childhood. So does my sister mom aunts and uncle. They have all pretty much found what works for them and me…I get them the worst and most frequently of everybody. Triggers are definitely stress, disrupted sleep routine, SUN, dry climate, chapped lips, thinking about them( just kidding) I apply ice right away and that has works a few times, but I swear these things have their own agenda. I have had a very bad hot rash up my back the first time I ever started taking prescription acyclovir with l-lysine supplements . At the same time while taking vitamin B. I like the method of drying them out. Alcohol, tea tree oil, peppermint oil, carmex, l-lysine ointment (which used to work great, but now just doesn’t like abreva) when I was a kid living by the ocean, the sea water used to do wonders…now I live in the dessert and I swear the dry climate is killin me….well anyway..good luck to all. Hope you find what works for you.

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