The People's Perspective on Medicine

Could an Antiviral Drug Help Control Alzheimer Disease?

Is it possible that viruses like herpes could contribute to Alzheimer's disease? If so, would drugs that speed healing from cold sores or genital herpes help control Alzheimer's disease?
Lip infection with the herpes simplex virus

There is a growing recognition by neuroscientists that the brain is not a sterile organ. In other words, the brain has a microbiome just like the digestive tract. There are bacteria, fungi and viruses that populate our brain and central nervous system (CNS). For years, some researchers have suggested that herpes viruses might be associated with dementia and other neurodegenerative conditions. Is there any way antiviral drugs might help control Alzheimer disease?

Would Drugs to Combat Herpes Control Alzheimer Disease?

One reader asked this questions:

Q. I have read on your website that herpes infections have been linked to Alzheimer disease. If there is a connection, would taking an antiviral medicine (one that combats both cold sores and genital herpes) be helpful?

A. You are asking a brilliant question. Scientists have been proposing that Alzheimer disease may be linked to herpes infections (Neuron, June 21, 2018). Here, in the authors’ words, is their overview:

“Investigators have long suspected that pathogenic microbes might contribute to the onset and progression of Alzheimer’s disease (AD) although definitive evidence has not been presented. Whether such findings represent a causal contribution, or reflect opportunistic passengers of neurodegeneration, is also difficult to resolve…

“We observed increased human herpesvirus 6A (HHV-6A) and human herpesvirus 7 (HHV-7) from subjects with AD compared with controls. These results were replicated in two additional, independent and geographically dispersed cohorts.”

How Could Antiviral Drugs Help Control Alzheimer’s Disease?

The peptide that makes up amyloid plaques typical of Alzheimer disease appears to be the brain’s way of fighting infection. Learn more about this in our free one-hour radio interview with Dr. Robert Moir and Dr. Dale Bredesen. It is Show 1132 available online at

Some physicians suggest that antiviral medicines should be tested as a way of treating Alzheimer disease (Frontiers in Aging Neuroscience, March 6, 2018).

“This review focuses on research in the areas of epidemiology, neuropathology, molecular biology and genetics that implicates herpes simplex virus type 1 (HSV-1) as a causative agent in the pathogenesis of sporadic Alzheimer’s disease (AD)…

“Studies are reviewed supporting subclinical chronic reactivation of latent HSV-1 in the brain as significant in the pathogenesis of AD. Finally, the rationale for and importance of clinical trials treating HSV-1-infected MCI [mild cognitive impairment] and AD patients with antiviral medication is discussed…

“By halting the direct and indirect toxic effects of HSV-1 on neuronal cells, antiviral medication may play a role in the prevention and treatment of AD.”

Studies Looking at Valacyclovir to help Control Alzheimer Disease:

In fact two clinical trials are recruiting study subjects to test the antiviral drug valacyclovir. One is at the New York State Psychiatric Institute and the other is at University Hospital in Umea, Sweden. Learn more at

In The Meantime?

It will likely be years before we know if anti-herpes drugs like valacyclovir do anything to help control Alzheimer disease. We are glad such research is now under way. In the meantime, we received an intriguing message from someone who read our newspaper column on this topic:

Karen in California writes:

“In reading your article about antiviral medication and Alzheimer’s – I would like to add another suggestion. I just retired as an engineer. I am a woman of a certain age. I feel mentally alert and grateful because dementia runs in the female side of our family and my only sibling is showing signs.

“When I was 35, I had an extreme bout of herpes that lasted 2 months and affected a quarter of my lips. I researched and found L-lysine as something that could combat the extensive lip flare-up. My herpes infection finally started abating.

“I decided to make L-lysine a regular part of my vitamin regiment and for 35 years have taken 500 mg daily. When the occasional (yearly or so) signs of a cold sore start to show, I up my dose. Perhaps rather than an antiviral med, L-lysine could play a role that may also help control Alzheimer’s disease as a spin off benefit.”

Share your own thoughts on this intriguing relationship between herpes viruses and Alzheimer disease in the comment section below.

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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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So I used to take 1000 mg of l-lysine daily and it did keep the cold sores at bay. However, I read an article that people with high cholesterol should NOT take lysine as it can be dangerous for those with high cholesterol and my cholesterol is VERY high. So I now use Nutribiotic GSE skin ointment with lysine. I put it on my lips morning and evening, and if I start feeling that tell-tale tingling I will increase the usage to 4 or 5 times a day. I have not had cold sores since I started using this product.
So questions:
1. Does lysine increase your cholesterol?
2. Will using lysine topically thus preventing a herpes outbreak reduce the risk of alzheimers?

I started L-Lysine approx. 40 years ago for the prevention of cold sores and never had another outbreak. I contracted HSV2 35 years ago and the Lysine did absolutely nothing to prevent genital outbreaks which were frequent and eventually outbreaks spread beyond that immediate area, Eight years ago I went to an immunologist who prescribed 800 mg, acyclovir twice daily. I have continued the lysine (500 mg. twice daily). Have not had one outbreak since. It would be great that there is the additional benefit of Alzheimer’s prevention with this regimen.

I too have taken L-lysine for years. I have carried the cold sore virus and have had some horrific outbreaks. When I feel the first tingle I take 1000mg then follow with as many as 6 doses a day. It stops the cold sore almost immediately. I have shared this information with many others

This is just anecdotal experience, but may be noteworthy. My husband (89) had herpes outbreaks which originated behind his ear and down one side of his face off and on for years. He also developed trigeminal neuralgia around age 70, which after years of meds to treat the pain, opted to undergo surgery to correct the problem. The brain surgery involved removal of the trigeminal nerve bundle, which alleviated the horrific pain and ended the debilitating effects of the pain meds (gabapentin). It also stopped the herpes outbreaks, which correlated with the herpes virus lying dormant in the trigeminal nerve bundle.

Why this information is so relevant to me is because at his age of 89 he shows no sign of AD despite the fact that both his sister and brother died from Alzheimer’s complications, and his mother had senile Dementia when she passed at the age of 99. He also has a nephew (60’s) suffering from AD. So maybe the removal of that trigeminal nerve bundle spared him the ravages of AD, when there’s a strong suspicion of a genetic abnormality in his family.

I take 1000 mg. Lysine on an empty stomach in the morning for herpes 2. So I can eat as many nut, seeds, and coconut as I want. Which is a good thing, since I’m vegan. Also, I take lemon balm extract, which is also good for herpes. I stay symptom-free.

This is very interesting. I’ve been taking Acyclovir for years due to significant bouts of cold sores. While taking this I’ve had no outbreaks. My dad (and our entire family) suffered from Alzheimer’s. I don’t remember him ever having cold sores. My mom does. I’ll certainly pass this information on to her. And keep taking my Acyclovir.

Can you tell me more about L-Lysine before I add it to my vitamin regimen. Does it have any drawbacks? Does it react with any common vitamins or medications? What is a common dosage?

thanks Bonnie

I have seen several articles about turmeric and the low rate of Alzheimer’s disease in India, Just wondering, could the antiviral properties of the turmeric in their diet have something to do with this? Maybe turmeric and Lysine together would be even more effective.

I think the l-lysine hypothesis for limiting the development of Alzeheimer’s is intriguing. I, too, have taken l-lysine for decades since it was suggested by my chiropractor as a way to treat and prevent cold sores. My mother had cold sores too, and I suspect I contracted the virus from her. She died with dementia, we never got a definitive diagnosis of the cause of the dementia but since learning about the herpes-Alzeheimer’s possible link I have been hopeful that I might be limiting my risk of developing the same condition.

I have been taking Lysine for years to prevent Herpes Simplex outbreaks on my face (left cheek). At the first tingle, I immediately take one Lysine tablet with food. Of course, if the Lysine does not stop the tingling and an outbreak, I take my antiviral. These two products also have worked with two shingles outbreaks in the past few years. I also have found that nuts, seeds, coconut and coconut water trigger the Herpes Simplex; so, I try to stay away from them. If I do eat some nuts, I take a Lysine tablet while eating them. I haven’t heard much about the nut connection through TV and radio programs, but since nuts are in vogue right now for good nutrition, I think people who are dealing with Herpes and/or Shingles should know about Lysine and the potential problem with nuts and seeds.

I have been taking l-lysine for about 8 years on and off. Used to get about 5-6 cold sores a year but now that I take L-Lysine I have had only 1 event in the last 4 years. When the first tingle of a cold sore comes. It stops it in its track. I also found uncooked walnuts will cause the roof of my mouth to break out in sores. The L-Lysine stops that also.

I think that people should pay attention to the work of Dr. Dale Bredesin and others who have successfully reversed Alzheimer’s with proper nutrition and lifestyle changes. There’s not the same money to be had as in restoring people’s health properly- no grants for trials or huge profits from putting so many people on drugs – but it’s the most ethical thing to do. Oh, and processed food producers may lose out, too.

One of the largest questions is whether valacyclovir and other drugs (plus L-lysine) actually “penetrate” the CNS and produce effective levels in the cerebrospinal fluid and brain tissue. Lysine is a very small molecule, for example, and may thus penetrate much better (there are other factors in addition to molecular size, of course).

So herpes type 1 (cold sores usually occurring on the mouth) is implicated with AD but herpes type 2 (usually genital herpes) is not implicated? Am I correct?

I also use L-Lysine on a regular basis, and like Karen in California, up my dosage when the occasional bout threatens. Unfortunately, it hasn’t been 35 years that I’ve been using it, but perhaps it will help anyway. Before finding out about L-Lysine, I tried various other home remedies (mainly from your website – thank you so much for having this site!), but none of them worked for me. (I have the kind of cold sores that are inside the mouth, but I’ve been told they’re still from Herpes.)

Again, thanks so much for all you do on your website!

I too have suffered with ulcers in my mouth. I have found that Carmex will eliminate them.
I put a tiny dab on the end of my finger and hold it on the spot for about 15 seconds each treatment. If I catch the sore before it has opened it is not likely to be an event. If I catch it right after it has opened, it may take a few applications to eliminate it. With active sores, I treat about 3 to 4 times daily until it is eliminated.

How would that explain the genetic factor? My husband is the 6th of 10 children and the 4th to suffer from Alzheimers. The Apoe4 gene is present. Perhaps AD is more than one disease?

It’s the other way around. Dementia is definitely more than one disease. Alzheimer’s and the APOE 4 gene is one cause of dementia. Others are, medication interactions, atherosclerotic changes in the brain, heavy metal and chemical toxicity and hepatic encephalopathy from advanced alcoholism to name a few.

AD is definitely not a simple disease. It has multiple risk factors. The APOE4 gene increases the risk, and other factors then set the disease in process.

I agree with Karen from California. I always used Lysine when I felt that a cold sore was coming on, and it either shortened the healing time or else stopped the cold sore from developing. I also take Lysine (one 500 mg capsule) a lot. I think I’ll start taking it daily and see what happens. A good friend of mine, who later developed Alzheimer’s, often had cold sores. Maybe researchers are on to something. I hope so.

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