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Desperate for Help With Recurrent Cold Sores

We've been flooded with letters from people who swear that the supplement lysine is their go-to solution for getting rid of recurrent cold sores fast.

Have you been troubled with recurrent cold sores? The herpes simplex virus (HSV1) that causes cold sores, aka fever blisters, never really goes away, but it can go into hiding for months or longer. If the immune system lets down its guard, the result can be painful lesions on or near the lips.

Presumably, we call them cold sores or fever blisters because they tend to occur when you have a cold or a fever due to infection. But we feel that is a misnomer. People can experience an outbreak in the summer when they get too much sun. 

The Yin-Yang Balance and Recurrent Cold Sores:

Stress can also trigger herpes lesions. Somehow, the immune system is not able to keep the herpes virus in check. Chinese researchers have offered an impressive explanation for how this happens (Acta Pharmaceutica Sinica B., March, 2020). Their article is titled:

Disturbed Yin–Yang balance:
stress increases the susceptibility to primary and recurrent infections of herpes simplex virus type 1″

The authors point out that the herpes virus has been linked to:

“…nervous system degenerative diseases like Alzheimer’s disease (AD). Reactivation of HSV-1 will increase the risk of developing AD…It might likewise be the cause of Meniere’s disease, an inner ear disease with spinning sensation, loss of hearing, and pressured feelings in the ear. Hence, all these findings have emphasized the importance on the study of HSV-1 latent infection.”

They conclude that:

“When the Yin–Yang balance maintained in latency is disrupted by stress, HSV-1 enters its reactivation cycle and causes recurrent diseases. Stress induces the reactivation of latent HSV-1 through multiple mechanisms. When the stress is removed, the latency will be re-established due to the re-silenced viral genome.”

Most American health care professionals have not been trained in the Yin-Yang balance. As a result, physicians don’t understand why the virus moves from the trigeminal ganglia in the brain where it has been “hibernating” down our nerves to our lips. Prescribing stress reduction may seem like a quaint concept to them. They are much more comfortable prescribing an antiviral agent.

What Can You Do about Recurrent Cold Sores?

Q. I have always suffered from recurrent 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 cold sores 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. Acyclovir (Zovirax) and penciclovir (Denavir) are available in cream form. In addition, your doctor could prescribe oral anti-virals as famciclovir (Famvir), valacyclovir (Valtrex), and Zovirax.

A Reader Likes Antivirals!

For years I have taken Zovirax or Valtrex to stop fever blisters. If I take either one when I first notice the irritation, it stops the fever blister right then. Amazing! I thought your readers would like to know.

We appreciate this anecdote. Such antivirals represent an extraordinary advance in pharmacotherapy. Want to learn more about why such drugs are exciting? Here is a link to our article about anti-herpes treatments against Alzheimer’s disease:

Can Anti-Herpes Treatments Prevent Alzheimer’s?
There is growing evidence to suggest that herpes viruses contribute to dementia. Could an antiviral supplement or drug like Valtrex prevent Alzheimer’s?

L-Lysine for Cold Sores:

If you prefer a more natural and affordable approach, you may want to seriously consider l-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 found in good quantities 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.

The Science of L-Lysine for Recurrent Cold Sores:

We were somewhat skeptical of this approach as there have been both negative as well as positive studies with lysine. Most of the research is with small numbers of patients and seems 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.

A review of the published research concluded that people need to take at least 3 grams (3,000 mg) of l-lysine daily to see benefit against cold sores (Integrative Medicine, June 2017). As a precaution, the authors suggest that people with gallbladder disease should avoid l-lysine. 

L-Lysine Testimonials:

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. Below, 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. 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 people about l-lysine?

For 50 years, I would develop fever blisters every time I went out in the sun. About four 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 wrote,

“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. If you would like to learn more about the connect between herpes infections and Alzheimer’s disease, here is a link you may find intriguing

Do Cold Sores Increase the Risk for Alzheimer Disease?
Herpes simplex type 1 infections cause cold sores and reactivation of the virus has been linked to Alzheimer’s dementia.

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About the Author
Joe Graedon is a pharmacologist who has dedicated his career to making drug information understandable to consumers. His best-selling book, The People’s Pharmacy, was published in 1976 and led to a syndicated newspaper column, syndicated public radio show and web site. In 2006, Long Island University awarded him an honorary doctorate as “one of the country's leading drug experts for the consumer.”.
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  • Mailoo VJ et al, "Lysine for Herpes Simplex Prophylaxis: A Review of the Evidence." Integrative Medicine, June 2017.
  • Tzeng, N-Z, et al, "Anti-herpetic Medications and Reduced Risk of Dementia in Patients with Herpes Simplex Virus Infections," Neurotherapeutics, April, 2018, doi: 10.1007/s13311-018-0611-x
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