The People's Perspective on Medicine

Will L-lysine for Cold Sores Protect the Brain from Alzheimer’s?

Harvard researchers have come up with a novel hypothesis about the cause of Alzheimer's disease. A reader wonders if L-Lysine for cold sores could help?
Lip infection with the herpes simplex virus

A connection between cold sores (caused by herpes simplex virus type 1 or HSV-1) and Alzheimer’s disease has been tossed around for decades. How good is the evidence? This reader would like to know if L-lysine for cold sores might be worthwhile.

Q. I have a family history of Alzheimer’s and have been doing a lot of research on how to try to prevent it. I just read that cold sores and other infections may contribute.

This is quite upsetting to me as I get cold sores frequently. I have started using L-lysine tablets to reduce outbreaks. Is there any evidence that it will protect my brain?

A. A recent study from Harvard offers a novel theory on Alzheimer’s disease (Science Translational Medicine, May 25, 2016).  The conventional view holds that plaque made of harmful beta-amyloid protein destroys neurons.

The new hypothesis suggests that beta-amyloid protein is part of the body’s immune response to pathogens as varied as those that cause cold sores, Lyme disease or HIV. It appears to act as a natural antibiotic, but it can cause damage when the immune response goes haywire.

Gina Kolata of the New York Times (May 25, 2016) explains it this way:

“Could it be that Alzheimer’s disease stems from the toxic remnants of the brain’s attempt to fight off infection?

Provocative new research by a team of investigators at Harvard lead to this startling hypothesis, which could explain the origins of plaque, the mysterious hard little balls that pockmark the brains of people with Alzheimer’s.”

Cold Sores (HSV-1) and Alzheimer’s Disease:

For more than 40 years scientists have been reporting an association between herpes virus infection (HSV type 1) and dementia (Alzheimer’s & Dementia, June, 2015).  In the 1980s a pathologist by the name of Melvyn J. Ball, MD, suggested that the virus that causes cold sores invades tissue within the central nervous system called the trigeminal ganglia. He hypothesized that the virus moves in two directions when it is activated. It migrates down nerves to the lips or face to trigger a classic cold sore and may also travel up into the brain to cause damage there in the form of neurofibrillary tangles. You can read much more about Dr. Ball’s research on herpes and Alzheimer’s disease at this link.

Another possibility is that the immune system reacts to the presence of the herpes virus by creating plaques and tables. This is the hypothesis put forth by the Harvard researchers in Science Translational Medicine.

L-Lysine for Cold Sores?

We don’t know whether treating cold sores with L-lysine or antiviral drugs (acyclovir, famciclovir, valacyclovir) would help reduce the risk.

There has been very little research on the effectiveness of L-lysine for cold sores. We did find this study about L-lysine for HSV-1 infections (Dermatologica, vol. 175, no. 4, 1987).  There is clearly no consensus from the medical community about this amino acid. It is essential for human health and is a building block for protein formation, but the question of whether it will help control herpes outbreaks remains surprisingly unanswered.

One theory of the antiviral mechanism behind L-lysine for cold sores has to do with its ability to inhibit the action of arginine, another amino acid. Arginine is important in the replication of the herpes virus. Supposedly, L-lysine suppresses HSV-type outbreaks by keeping the virus from multiplying.

Without big, well-controlled clinical trials we are unlikely to get an answer to the controversy of L-lysine for cold sores. After all, no drug company would spend millions on a study for which no profit could be made. In the meantime, all we have are anecdotes. Many visitors to our website do report that L-lysine can help prevent cold sore outbreaks. Here are just a few of the stories we have received over the years:

Janet, Palm Beach County, FL, writes:

I have suffered with cold sores since I was a child. As an adult, I worked in several hospitals, and the chief pharmacist in one suggested all the possibilities he had heard of that could help.

“It wasn’t until several years later that I heard about L-lysine. I bought it and tried it. What a blessing!

“At the first tingle, I take 1000 mg in the morning and another dose before bed. The blisters never even form! I’ve been caught by surprise when traveling, and by the time I could get to a drugstore the blisters had all formed. By starting out doubling the dose the first day and then dropping back to the 1000 mg level after that, the blisters actually go back down — no sores or scabs.

“Now I’ve found the 500 mg capsules are easier to swallow, and still work as well. Thank heavens for L-lysine for cold sores. I have also heard of several physicians who knew about L-lysine and are recommending it to patients with shingles to help reduce the pain and length of the outbreak.”

Ruth offers this long-term experience with L-lysine for cold sores:

“I had cold sores all the time but then I added 500mg L-lysine to the vitamin that I take. I am 70 years old and have not had a cold sore in 30 years. If I do feel a warm spot on my lip I take an extra 500mg L-lysine and the warm spot disappears.”

Art offers an interesting perspective:

“Q. What’s the difference between love and herpes?

“A. Herpes lasts forever!

“The Herpes Simplex Virus (which was once known as,”The Kissing Disease,” which is why the Roman Empire of old prohibited kissing among their legions) and which some 80% of Americans carry, is what causes cold sores on the mouth.

“Once the virus is initially contracted from an infected person or infected object, the virus travels to, and permanently resides in the trigeminal nerve and reoccurs periodically, usually triggered by stress, certain types of spicy foods, sunlight, etc. in episodic outbreaks.

“The initial outbreak can be quite painful, unsightly, and lasts for 7-10 days.

“Subsequent outbreaks, while still painful, will generally become less severe over the course of time.

“Home remedies help alleviate the pain and discomfort and help to shorten the duration of an outbreak.

“L-lysine, an over the counter supplement, works well in the long run by bolstering your immune system. L-lysine is quite affordable and free of any side effects that I know of.

“The home remedies mentioned on the People’s Pharmacy website by contributors to the site, are good for treating the symptoms of herpes labialis, another name for cold sores.

“Whatever works for you I say!”

Other remedies for cold sores:

We have collected lots more home remedies for cold sores on our website. They include kiwi fruit, buttermilk and ice to name just a few. Here is a link. And if you like the idea of home remedies for a variety of common ailments, we encourage you to check out our book, The People’s Pharmacy Quick & Handy Home Remedies. There is a reason why readers have given this our highest rating, 4.9 stars out of a possible 5 stars.

Bettie in Wilkesboro, NC sums it up nicely:

“I love the book. I use the mustard for leg cramps often and it always works; also the cough (Vicks on the feet) which also works). I also tried the raisins before bedtime and only had to get up once [to pee]. Thank you so much.” 

Read other comments at this link.

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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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I had herpes outbreaks during my teens, mainly in the spring. But started drinking a lot more milk for my bones and then had rarely any outbreaks. In recent years when I was drinking lots of soy milk they started a bit again. I had to stop soy foods for other reasons and restarted yogurts so the outbreaks stopped again. I wasn’t really aware of the reasons. But I noticed over the last few years that zinc supplements also stop the virus in its tracks. I take a lot of zinc for histamine intolerance, and whenever I take less the tingling starts again. So I quickly go back on my full zinc regimen.

I’ve never had a cold sore. But the big question in my mind is whether other Herpes-class viruses, like those that cause mononucleosis and chicken pox, also increase one’s risk for Alzheimers? Why would it be just the cold sore virus?

During teens had my first outbreak of cold sores, all over mouth and down to chin on one side — I refused to go to school or outside house. Somehow learned about the lysine-arginine inverse ratio so started taking 50 mgm lysine daily–hooray not more outbreaks! The only times I’ve had an outbreak is when I’ve been out of or forgotten to take lysine. Then, recognizing the itching/tingling for what it is, I take 2000-4000 per day for several days then taper to 1000 per day then to usual 500/day. Now in my 60s, I take it combined with 500 mgm l-proline for blood vessel integrity. I have taken Denavir prescription but it doesn’t work any better that the huge amt of lysine. Mom with Lewy-body dementia passed (she had one herpes 12 outbreak & would not take lysine). I have the same eccentric responses to drugs so I hope my daily lysine (and monolaurin supplement) will be protective. I also avoid veggy oils, cooking instead with organic and refined (no chemical distillation) coconut oil. Sharing hoping this will convince others to try lysine.

“…new research by a team of investigators at Harvard lead to this startling hypothesis…”
Well, “led to…” actually. “Lead” is a heavy metal used by plumbers.

My solution does not require medication for curing cold sores. You must try it to be a believer as the many people I have told this to have found to be true. We all know when we are about to have an eruption and it’s at this time when you must pinch an area that is very sensitive. I use the inside of my arm. The virus travels along nerves and when you pinch an area where it really hurts, the sensation from the cold sore tingling is blocked by the pinching and zaps the cold sore in its tracks. It does work!

I find L-lysine very effective for cold sores. I read recently that prevention is best, so I now take a 1,000 mg tablet each morning with breakfast. Having studied biochemistry long ago, I hypothesize that the herpes virus needs arginine to build its protein coat. Lysine is similar in structure to arginine; perhaps when there is more lysine than arginine, it inhibits the virus’s ability to replicate. If I do get the beginnings of a cold sore, I increase the dose to one tablet with each meal. I also try to avoid foods high in arginine, such as nuts and chocolate, when I have a cold sore.

I have Lichen Planus and began taking L Lysine after reading about some of the results folks have gotten for cold sores. I get canker sores and take 1000 mg a day. It works. When I have forgotten to take a dose I can feel the beginnings of the sores, but as soon as I take the tablet they do not erupt. This has been a blessing for me after years of misery.

Kuddos to you for publishing this. I have been taking L-Lysine for years. I can’t remember my last cold-sore. I had shingles one time many years ago and took L-Lysine (2 grams) daily. It took one day for the pain to end and about two days for the rash to disappear. I explain the efficacy of L-Lysine this way: The Herpes virus requires L-Arginine to replicate itself. Somehow, the virus recognizes L-Lysine as if it were L-Arginine. The L-Lysine prevents viral replication.

My husband & I both take Lysine and it works wonders. If we do get a cold sore, the duration is so much shorter and they don’t even hardly show.

I have been having a problem in my nose, which I thought might have been caused by a scratch. While I was at the doctor for something else, I asked him to look at my nose and he told me it was a cold sore. In the nose! We both said lysine at the same time. Those capsules are huge and hard to swallow. But it went away. However, I have been prone to constipation all my life, even as an infant, which was cured by using essiac tea and stool softeners. Lysine brought it back. Now I take it every Monday as a preventative.

Years ago a veterinarian diagnosed my cat with herpes in her eye and prescribed L-lysine supplements (1/2 capsule every other day), which has kept the problem at bay ever since. I did buy a house brand once and while taking that her symptoms came back, but when I switched back to a national brand her symptoms subsided again and have not re-emerged.

It’s been proven that the store generic vitamins might only have traces of the main ingredient so I only buy brand name like Nature Made.

I take 500mg of L- lysine a day plus a monolaurin capsule (from coconut oil) to prevent cold sores. It works for me. I still start the acyclovir if I get a tingle from genital herpes. It works the best.

I have been taking Lysine for cold sores for 30 years and it works. It stops it in two days and I have fewer cold sores.

The first time I have a little tingling l take BHT. It works faster than L lysine. I start off with four capsules at two a day for about a week. It also knocks out a flare-up of the herpes virus. However, L lysine is also good.

I think it’s a shame that we can’t have clinical trials for home remedies. Our lack of organization means that we will continue to depend on big pharma as the gatekeeper for our health. Collecting stories for many different people is better than nothing, but just imagine if we were organized and could conduct more scientific research? It wouldn’t be as strict or as well funded as what BF does, but it could provide more concrete information by providing a much larger dataset of results.

Excellent thought. It would be terrific if there was a research institute to examine simple and inexpensive disease prevention and treatments. Is it possible that something as simple as Lysine supplements could prevent Alzeimer’s? Since profit would not be a motive, perhaps the institute could be funded from charitable sources or even Federal assistance? Many common sense health “fixes” could be scientifically tested with no big pharma expensive new drug development costs. Thousands of online folks could become part of “clinical trials.”

I never had one in my whole life until I used MetroGel on my Rosacea. I kept using it and would have the most horrible cold sores that lasted 3 Weeks. I read (finally) the paper with it that said that could be a side effect. My dr. smiled, said there was an old-time relief in L-Lysine. I got it, 500 mg and it helped and in hospital without it after a surgery, got horrible sores again. BUT somehow that no Longer is listed on MetroGel as a side effect. I saw in Rosacea news letter that another person with Rosacea asked about cold sores, too. I take 500 mg. a day, every day. Try it- mom died of dementia. I had no idea of any connection. I am 79. She died at 73.

I can see the connection between cold sores and alzhimmers especially when we are aging! Cold sores appear due to immune suppression or depression and as we age as does our immune systems in other words our bodies are no longer able to make DNA repairs to tau protein. I would also connect the dots between latent chicken pox vaccine outbreaks which manifests into shingles later in life there obviously could also be a connection between chicken pox vaccines and the occurrence of cold sore type poxes. Just a phenomenon which is said to be idiopathic but all phenomenon has both cause and effect !

Veterinarians seem to be ahead of the game. Some have been telling their clients to give L-lysine to their cats with herpes. Herpes manifests as a respiratory condition in cats. I have a cat with herpes and he gets 500 mg per day split between two meals (I crush half a tablet and put it in his canned food). I can tell you it works very well, as he’s had no outbreaks since being on L-lysine.

I have abnormal nerve conduction and have been diagnosed with idiopathic peripheral neuropathy. My feet and thighs sting and tingle most of the time. It is worse at night, thankfully, so I can function in daytime. Any ideas?

You might try benfotiamine (300 mg twice a day) and/or alpha lipoic acid 600 mg/day. Here’s a link to more info:

I just wanted to mention ice which works 100% for me. At the first tingle, get an ice cube, or cold pack from the freezer and hold it on the area for 20 minutes. That’s it.

Yes, ice (along with daily Lysine) works for me as well. Ice seems to ‘kill’ the virus (or at least inactivate it) because of the temp the virus needs to survive. I’m glad to hear of another person who uses ice with an outbreak.

My wife gets cold sores. We have been married for 37 years, and she had a cold sore when we got married. One thing that she has discovered: eat yogurt every morning, without fail, and she does not get any of the cold sores!!

A diet high in dairy products helps. Dairy has a very high lysine to arginine ratio, which suppresses the virus. A lysine supplement would probably do the same.

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