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. debi

    I suffer with coldsores a lot I av just gone and bought l-lysine I really hope they work fingers crossed .

  2. John

    Ive dealt with them my whole life – usually 1-2 a year, but they would be really bad when i got them. Like 2 weeks to heal. Lysine never worked for me personally. Doc gave me a Valtrex prescription about 10 years ago and its made a world of a difference. As long as i take 2 1gm pills twice a day right when i see it, it never gets bad, and is gone in 3 days or so. I make sure to have a few on me at all times.

    However, just recently, im dealing with a bout of back to back breakouts – like 4 straight weeks now. The prescription is still preventing them from becoming bad, but the recurrence is frustrating. Im wondering if my immune system is down or something. My diet and stress has caused problems in the past, but never this many. In the last 4 weeks, I’ve gotten more than i had in the previous 4 years.

  3. Dawn

    I used to get cold sores about twice a year. Then someone told me about L-Lysine-I started taking it and it seemed to work well for a while. I take L-Lysine every day and for the past 8 months I have been getting cold sores about every 6-8 weeks! I am so tired of this…

  4. ashley
    Kalamazoo mi

    I used to get cold sores twice a year, one when it got hot outside, and one when I got cold outside. They were often big and ugly, but since starting lysine tablets, I havent had one! I don’t even have to take them every day. Only when I feel “the tingle” or when the area I normally get them starts to look red. I also couple that with an application of abreva, and viola, no cold sores for a year now. I’m a believer!

  5. Stephanie

    I’ve noticed when I eat/drink oranges, OJ, grapefruit I break out. I don’t know if it’s just coincidence but I love these foods especially in the summer but try to avoid them as much as possible. I’m going to try icing it and I’ve heard garlic works too. Has anyone tried garlic directly on a cold sore?

  6. Chloe

    After reading this chain and seeing all the comments about icing early cold sores gave it a go this morning. Have been getting them for 3 years now and lately they have been continuous, its awful. Zovirax, aciclovir tablets and lysine have not worked. Happy to say that after icing my lip for 2min this morning (followed by zovirax ointment) the 2 new sores have completely disappeared!!! Will repeat this afternoon, fingers crossed they stay away.

  7. Jodie
    United Kingdom

    I regularly get cold sores. I have been using compeed cold sore patches. These are great, but can be noticeable when I am wearing foundation & make up. I always get them when exposed to the sun. I need a quick remedy to get rid asap.

  8. Haley

    In the beginning stages of getting a zit under my nose, I thought it was a cold sore. I started taking an antiviral once to twice a day, and taking lysine twice a day, as well as rubbing abreva on the spot. Even though it just turned out to be a blemish, I was continually doing everything you can do to prevent and treat a cold sore when I woke up with a cold sore on my lip. It made me want to cry. Not that I’m going to give up, but it seriously makes me doubt there is anyway to actually control this. I will say since I discovered antivirals I at least don’t get cold sores as giant and scarring as the ones I got in childhood when no one was looking how to really take care of this for me. But even with the time and money I’ve put into trying EVERYTHING as an adult, I’ve been 100% unsuccessful at actually preventing an outbreak.

  9. ashley

    I first had a cold sore in the middle of my first pregnancy. I have no idea how I go them. I struggled for over two years with constant reoccurring breakouts. I started dealing with it by taking lysine. At first it seemed to help but soon seemed to be little help and I was still having frequent outbreaks, at least once a month. So I asked my doctor for a prescription of Valtrex. Since on valtrex, one year now, I have had three minor outbreaks, I think mainly due to missing a dose. It has been very effective for me. I take just 500mg a day. I hope to go back to something more natural but this is all that works for me currently. Lysine wasn’t effective enough for me

  10. Corey

    For me, lysine definitely worked. I started taking lysine and didn’t have a breakout for a year and a half. When I did sense a breakout, I pumped up the dosage and the cold sore wouldnt be that noticeable. But, now the problem is, I just moved to Colorado and I’ve been getting chronic cold sores. I’m not sure if it’s just my body acclimating to the dry environment or if my body has become immune to the lysine. Hopefully, it is just me adjusting.

    • Lisa

      I was doing well in Florida. I was going to the beach and the sun for a change wasn’t bothering me at all. Now that I have moved to Colorado, been here a month, I am already on my second outbreak! I am starting to think it has something to do with Colorado also.

      • Jess

        I also came to Colorado from Florida last year, and was in Malaysia before that. Almost a year with no outbreaks. Since coming to Colorado I’ve had an outbreak every month like clockwork, & no idea why. I eat well, and get more exercise than I have in a while. Totally stumped, too! Could it be the altitude??

  11. sherley
    rochester ny

    I use l-lysine- tea tree oil – garlic fresh- vanilla extract- alcohol- coconut oil-honey to no avail as soon as the first one started to heal up under my nose I got 3 more pumps on my lip I never eat nuts or bread put I just started eating fresh pineapple and the next day they started and I have been eating it everyday for the vitamin c I wonder if that’s what causing it?

  12. Alex

    So this may sound extremely out there, but I’m almost certain the Gummy prenatal gummy vitamins from Target keep my cold sores dormant. It could just be taking any multivitamin will do the trick of a lack of nutrients is causing your cold sores. The prenatal ones are just the ones I’ve always taken (for the extra benefits they provide for your skin and hair). But before I figured this out, I was suffering from persistent, reoccurring cold sores in the year and a half I stopped taking the vitamins. I would get one, it would heal, two days later a new one would sprout up on the other side.

    That being said, I figured out a pretty solid regiment for getting a cold sore gone fast. It’s even kept them from blistering. The second I feel a tingle I take a lysine. After I know for sure its a cold sore, I take two more. And then continue taking two every 4-6 hours. I also take extra vitamin c and zinc to boost my immune system. (Always take with a meal, or you may get sick, and drink LOTS of water.) I also ice the spot as much as possible, especially after a nice warm shower. I used to never do this, but gave it a shot and found it to truly be a game changer. I also put on abreva just for peace of mind when I’m out and about.
    Hope this helps!

    • Haley

      I religiously take multivitamins (very specifically the prenatal a from target as well) and can tell you they don’t work, unfortunately. Though boosting your immune system can only be helpful.

      Pineapples, especially fresh, tends to really (tear up) your mouth. The acid causes tiny abrasions in your mouth, and then cold sores take advantage of your immune system being diverted taking care of that to set up shop else where around your mouth.

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