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. Lora
    Arlington,WA
    Reply

    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.

  2. Lynn
    Omaha
    Reply

    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.

  3. Little Lumatic
    Victoria BC
    Reply

    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.

  4. Sam
    Reply

    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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