Cold sore prevention - How lysine and other treatments ignore the true cause of recurring cold sores

If you are looking for a cold sore prevention strategy that actually stops outbreaks from coming back every few months or even every few weeks…

Then the information on this page may be able help you finally put an end to your recurring cold sores by stopping them on a deeper level than lysine, pharmaceuticals, or any other cold sore prevention treatment you’ve used in the past.

Now, maybe you already know what I’m about to talk about.

But if you don’t, I’m here to tell you that if what you tried in past for preventing cold sores didn’t work, just know that it’s not your fault.

It’s not that you did something wrong, that you ate the wrong foods, or that you did on purpose to trigger yet another cold sore.

It’s that you’ve been operating on the wrong information.

Word of warning: this page is NOT about how to prevent a cold sore when it first starts or when you first feel it coming. Check out our cold sore treatments page for information on that.

With that out of the way, let’s move on.

Have typical cold sore prevention methods failed you in the past?

See, I believe most cold sore prevention methods being proposed these days just don’t work.

At least, not on the level you need them to.

Things like taking lysine supplements, avoiding arginine, taking expensive pharmaceuticals, taking weird herbal supplements said to possess antiviral properties, homeopathic remedies, trying to find your elusive triggers, etc.

All of these fail because not one of them addresses the actual root cause of recurrent cold sores.

See, according to a recent yet little-known scientific discovery, there is a specific biochemical “signal” that gets triggered right before you get a cold sore. And it is this signal that awakens the herpes virus which, in turn, causes a cold sore.

Now, if you could stop this process from happening, you’d be able to prevent the herpes virus from reactivating in the first place. And if it can’t reactivate, it’s literally impossible for it to cause a flare up.

You stop the root cause.

That’s what I call true cold sore prevention.

But instead of doing that, most cold sore prevention treatments focus on stopping the herpes virus AFTER it has reactivated.

That’s not true prevention. It’s putting out fires as they happen.

Now, I think you’re familiar with what happens when you don’t address the root problem of recurring cold sores.

No matter what treatment you use, cold sores still keep coming back

It seems that no matter what treatment, diet or supplement you try to prevent cold sores, those outbreaks just keep coming back.

Sometimes every few months.

Sometimes EVERY month.

But sometimes the herpes virus does leave you alone for a while. You can go months without an outbreak.

And at that point, you think that what you’re doing may actually work!

Until you wake up one morning and BOOM! Cold sore.

From there it’s a mad scramble to find an effective cold sore treatment to at least limit the damage.

The point it, you keep getting recurring outbreaks because your cold sore prevention strategy doesn’t address the root cause of the problem.

Do your cold sores keep getting worse over time?

When you aren’t doing anything to stop the root cause of the problem, your cold sores just get bigger and nastier every time.

See, the herpes virus doesn’t reactivate for no reason.

When it does reactivate, it uses the activity of that biochemical pathway I mentioned earlier as a sign that it’s time to wake up and multiply like it’s life depends on it.

To the herpes virus, that biochemical pathway is like a blaring warning alarm.

So in its mind, it’s just trying to survive, just trying to save its own ass and pass on its genetic material.

Just like all life forms.

But when your cold sore prevention treatments only focus on interfering with the replication of the herpes virus (like lysine supplements and basically all pharmaceuticals like acyclovir and famciclovir do), there’s nothing to prevent the warning alarm from going off in the first place.

Look, if you’re not doing anything to stop the things that trigger the biochemical pathway responsible for the reactivation of the herpes virus, what’s stopping those trigger factors from getting worse?

How are you going to stop them?

Do you even know what those factors are?

It’s like the saying goes: “The only thing necessary for the triumph of evil is for good men to do nothing.”

Same goes for cold sore prevention.

Do your cold sores tend to show up at the worst possible time?

And triumph they will, at the worst possible time.

Ever notice how cold sores show up right before a job interview… a date… a wedding?

The herpes virus is a master at bad timing.

If there’s an important date on your calendar, odds are good a cold sore is going to show up to ruin it.

Well, if you’re not preventing cold sores the right way by targeting the actual root cause of recurring outbreaks, then what is stopping them from ruining your life’s most important days and events?

Sure, you could just risk it. Hope and cross your fingers that you don’t get a cold sore.

But you know it’s a coin toss.

And until you start using a cold sore prevention strategy that works reliably, you have zero control over when they show up.

Hey, maybe you’ll get lucky. Maybe they won’t show up for important events.

Then again, maybe they will.

Are you living in constant fear of triggering yet another outbreak?

And that ever present threat is why you end up living in constant fear of accidentally triggering your next cold sore.

Always worrying if what you’re about to do is going to trigger a nasty outbreak.

Should go out with friends and have that drink?

Should you go outside in the sun?

Should you eat that?

Well, if you don’t know what factors are actually responsible for reactivating the herpes virus, it’s just impossible to avoid your triggers because you don’t actually know what they are.

Sure, you can guess and take cues from what you read online.

Avoid arginine, avoid coffee, avoid alcohol, avoid the sun, avoid stress…

So basically, you can’t eat chocolate, you can’t go out on a sunny day and you can’t have a drink with friends.

What kind of life is that?

On the other hand, if you understand how the herpes virus works, why it remains in latency and why it chooses to reactivate, you’ll understand how to truly prevent cold sores from coming back because you’ll understand what actually triggers them and why cold sores keep coming back in the first place.

There is a lot of power is knowing your enemy. It’s half the battle they say. And that applies double to preventing cold sores.

Prevent cold sores by understanding the latency stage

Like I said, if you really want to prevent cold sores from coming back, you have to prevent the herpes virus from reactivating in the first place.

But doing that requires that you understand a few things about the herpes virus.

Let’s take a look at how recurrent cold sores happen.

When you first get infected by the herpes virus, it forces its way into the skin cells in your lips, high jacks their cellular machinery and makes countless copies of itself (by the way, the reason it does this, like any other virus, is that the more copies of itself it releases upon healthy, uninfected “hosts” (healthy cells or other people) the higher its chances of survival. It’s a numbers game.)

Then, it runs through the 5 stages of a cold sore, which is when itchy, painful blisters appear to generally make your life hell, eventually turn into scabs and eventually fall off so things can return to normal.

Ok. One of the things that happens at the end of an outbreak is that the virus enters your trigeminal nerve (that’s a nerve in your face that is responsible for, among other things, making sure you can move the muscles around your mouth and feel your face). Then, it climbs up this nerve and makes its way to the ganglia, where it remains dormant until it decides to reactivate.

As long as the herpes virus remains in a dormant state of latency, it cannot cause a cold sore.

It’s worth repeating:

A dormant herpes virus cannot cause a recurrent cold sore infection.

If you remember only one thing from reading this page, make it be that. And it makes sense.

Say you’re the police and you just captured a crazy, dangerous serial killer. What’s the best way of making sure he never kills again, short of giving him the electric chair? You lock him up, and make sure he stays in his cell and can’t EVER get out.

That is the exact approach you need to take with the herpes virus and preventing cold sores.

How do you do that? Well, the obvious answer is you make sure to avoid the factors that cause the herpes virus to reactivate. And how and when does the herpes virus decide to reactivate?

Aha! Now you’re asking the right questions.

When and how the herpes virus gets triggered

In a nutshell, the herpes virus reactivates when it feels that it is being threatened in some way.

Threatened!? But wait, isn’t the herpes virus the one doing the threatening, what with it causing cold sores and stuff?

Not from its point of view. The way it sees it, it’s just trying to survive.

And when it makes its way up into your ganglia in between outbreaks, all it’s really looking for is a safe, cozy place to hibernate.

So the question becomes, what exactly signals to the herpes virus that it is being threatened in some way that makes it reactivate, swim down the trigeminal nerve, re-infect the skin cells in your lips, make copies of itself, and try to find a new safer place to live?

That is where the biochemical pathway I keep mentioning comes into play.

The herpes virus doesn’t have eyes. It doesn’t have ears, a nose or a tongue to sense danger. However, it does have a mechanism to detect when this biochemical pathway becomes activated. And THAT, is its signal that it’s time to wake up and cause a cold sore.

This is what you want to avoid at all costs if you want to prevent cold sores from coming back.

And this simple truth is that virtually ALL cold sore prevention treatments available today fail to do on any level whatsoever.

But don’t worry, there are alternative treatments and strategies that actually do prevent the reactivation of the herpes virus on this level.

Why most cold sore prevention treatments fail miserably

Have you ever wondered how most cold sore treatments designed to prevent future outbreaks actually work?

Almost without exception, they are designed to interfere with the replication cycle of the herpes virus.

They use molecules, compounds and amino acids that are supposed to hamper the ability of the herpes virus from using the cellular machinery inside your skin cells properly. That way, whatever replicated particles of the herpes virus are created are either broken or just non-functional, like a machine with broken cogs and hinges.

The logic behind these cold sore prevention treatments is if the herpes virus can’t make “healthy” copies of itself, it won’t be able to infect more healthy cells. This limits the breadth of the infection and either stops full blown cold sores from forming, of keeps them to a bare minimum.

However, the way I see it, there are three big flaws to this approach that nobody seems to be talking about.

  • For the herpes virus to replicate itself, it must be in an active state, and out of the latency stage. Meaning, that your typical cold sore prevention treatments do absolutely nothing to prevent the reactivation of the herpes virus. Instead, they are all about catching the herpes virus while it’s trying to escape, instead of making sure it stays locked up in the first place. That’s not cold sore prevention, that’s putting out fires as they come along.
  • Because you don’t know when the herpes virus is going to reactivate, you must constantly be pumping antivirals into your body, in the hopes that the re-awakening of the herpes virus overlaps with the presence of these antiviral compounds. And I don’t know about you, but constantly flooding your body with man-made chemicals with sometimes nasty side-effects doesn’t sound like the smartest long term strategy for your long term health to me.
  • While you are taking antivirals, you aren’t focusing on eliminating the factors that are truly responsible for reactivating the herpes virus. And the more you do nothing and let these factors get out of hand, the bigger the viral load you’ll be dealing with during subsequent cold sores is. And the bigger the viral load, the less effective your antivirals will be against your recurrent cold sores. That’s when you end up being forced to increase the dosage of your prevention treatment again and again because they “stop working” after a while.

And therein lies the big problem with most of the cold sore prevention treatments being recommended these days. They just don’t focus on the right target.

It’s not that they are not effective at what they do. It’s that they target the active state of the virus instead of trying to stop it from reactivating in the first place.

Don’t believe me?

Let’s break down what some of the most common cold sore prevention treatments do and how they fare in the light of what we just talked about.


Lysine is probably the most well known cold sore prevention strategy out there. It’s cheap, and even has some scientific evidence supporting its use as a cold sore prevention treatment.

The use of lysine against cold sores started in the early eighties when a team of scientists found that adding lysine to cells infected with the herpes virus inhibited the replication process of the virus.

Whether the results found back then hold up or not is a matter of debate. Since then, some scientists have found that lysine works, others have found that it doesn’t.

But it doesn’t matter. Because there is no evidence suggesting that lysine has any effect on keeping the herpes virus in a state of latency. Just that it may or may not interfere with the replication process of the herpes virus.

Avoiding arginine

After lysine, the most common advice for preventing cold sores you’re gonna hear is to avoid any and all sources of the amino acid arginine in your diet.

More specifically, you’ll read that it’s not so much about avoiding arginine, but consuming more lysine than you do arginine so as to keep a high lysine to arginine ratio (hence why people take lysine supplements).

Where does this treatment idea come from? Interestingly, it comes from the same studies that found that lysine interferes with the replication of the herpes virus. The scientists found that the herpes virus needs arginine to replicate properly. The logic therefore became that to stop it from replicating properly, just stop giving it what it wants.

But once again, blocking viral replication is not true cold sore prevention.

So what does this mean in practice? It means avoiding foods like nuts and seeds, most meats, chocolate, wheat oats and other grains, etc.

And heck, some people even go so far as to recommend that you avoid things like spinach, as it contains more arginine than lysine! As if the health benefits of spinach don’t outweigh the tiny little bit of arginine spinach contains.

What’s left that you can eat? Good question. Not much.

What people end up doing is avoiding a lot of foods that are actually healthy (despite their arginine content) or that they like eating (chocolate anyone?), all for something that probably does nothing to keep the herpes virus in a state of latency.

Look, even if arginine promotes the replication of the herpes virus, that just means that you should avoid it DURING an outbreak. But there’s no reason to avoid it for the purposes of cold sore prevention.

Plus, there’s an arginine elephant in the room that nobody seems interested in talking about. And that is the fact that the human body has the ability to MAKE arginine. Meaning even if you manage to avoid all sources of arginine in your diet, it’s still coursing through your veins and therefore still accessible to the herpes virus if it needs it.

You can’t avoid it, even if you try.

So stop trying. It doesn’t even actually help prevent cold sores.

Pharmaceuticals like acyclovir, famciclovir, etc.

When it comes to pharmaceutical treatments for preventing cold sores, acyclovir is probably the most popular.

It’s was discovered in the early nineteen seventies and used in a clinical setting since the nineteen eighties.

The way it works is it blocks the activity of HSV specific DNA polymerase, which is basically an enzyme that assembles the building blocks of the DNA of the herpes virus particles. It the DNA portion of the herpes virus cannot be assembled correctly, it simply cannot make copies of itself.

By all accounts, acyclovir works very effectively at blocking the replication of the herpes virus. The science backing it up is undeniable.

However, once again we are talking about replication. Meaning that for acyclovir to be effective at preventing cold sores, the virus must be out of its latency stage, active and replicating.

The work around here, like for most cold sore prevention treatments, is to take a daily dose of acyclovir in the hopes that the second the virus reactivates, its replication process gets blocked and the infection doesn’t go anywhere.

This is ok, so long as you’re good with taking a prescription pharmaceutical every day. A pharmaceutical that, by the way, that comes with a long-ass list of side effects:

  • nausea
  • diarrhea
  • vomiting
  • headache
  • dizziness
  • tiredness
  • muscle or joint aches
  • visual changes (hallucinations?)
  • fluid retention
  • hair loss
  • confusion
  • changes in behavior

Personally, none of those sound fun. As a guy in his mid thirties, I’m terrified of losing my hair and I’m grumpy enough as it is (especially when I’m hungry). I’m not about to risk those side effects for something that doesn’t even actually prevent the herpes virus from reactivating.

Look, I’m all for pharmaceuticals for alleviating symptoms. They do a better job at that than practically any other type of remedy in the world.

However, I’d rather use acyclovir only when it can actually be useful, like during a cold sore outbreak where the herpes virus is actually awake and replicating.

But when the herpes virus is in a state of latency? Acyclovir (or any other pharmaceutical for cold sore prevention for that matter) ain’t gonna do jack to keep it there.


Docosanol is the active ingredient in Abreva, which is the possibly the most common over-the-counter product sold today for the purpose of preventing cold sores.

The way it works is by blocking particles of the herpes virus from entering healthy skin cells in your lips. And if the virus can’t enter a healthy cell, it can’t replicate itself which limits the range of the infection.

The scientific evidence behind docosanol seems pretty solid, but when you read about the experience of cold sore sufferer’s, it isn’t unanimous. Some swear by it, others say it doesn’t work.

Regardless if it works or not, one thing is certain: it doesn’t keep the herpes virus in a state of latency. To have any effect whatsoever, the herpes virus must be active and trying to infect healthy cells.

Again, the only way to prevent an outbreak using docosanol would be to use it every single day, so that when the herpes virus does reactivate, it bumps up against the docosanol and can’t infect any healthy cells. But given that Abreva costs 20 bucks a tube, that’s not really practical.

That being said, I have seen new lip balms that contain docosanol popping up online which are way cheaper than Abreva. That could be a legitimate option.

However, know that it’s not true cold sore prevention.

When a cold sore does pop out, by all means use docosanol to limit the size of your cold sore.

But if preventing cold sores at their source by keeping the virus in a state of latency is what you’re looking for, docosanol isn’t going to help.

Ok. There are plenty more treatments being touted and/or sold for cold sore prevention purposes. Tea tree oil, lemon balm, propolis, ice, rhubarb, sage, and licorice root extracts, zinc, etc.

By and large, they all have the same common theme going on. They are all targeted against events that occur AFTER the herpes virus has reactivated and is trying to infect the skin cells in your lips.

But none of them will help you fight off the factors that cause the herpes virus from reactivating in the first place by triggering that biochemical pathway we mentioned earlier.

To me, that makes these treatments much better suited to fight off an impending outbreak. So when you feel that tingling sensation coming on, know that the cold sore treatments listed above can be very very useful.

Just don’t expect them to prevent cold sores from happening in the first place.

What about avoiding your cold sore triggers?

If most cold sore prevention treatments don’t actually stop outbreaks at the source, what else can you do?

In reality, to truly prevent cold sores, the only thing you can do is to stop the biochemical pathway that awakens the herpes virus from becoming active. In other words, you have to avoid your cold sore triggers and risk factors.

But have you ever wondered what exactly triggers a cold sore?

Just like when you ask what’s the best way to get rid of cold sores, asking what your triggers are will get you a smorgasbord of different answers.

Some say arginine.

Some say excessive sunlight.

Some say sugar.

Some say getting sick.

Some say your period (if you’re a biological woman, of course).

Some say coffee.

Some say alcohol.

Some say strenuous activity.

Some say junk food.

Some say certain vegetables.

Some say the color of our underwear.

Really, if you were to avoid all the things that people say trigger cold sores, you may as well stop living entirely. And I don’t mean living in the “go bungee-jumping with the dolphins” sense. I mean living living. As in breathing.

I mean, you have to leave the house at some point, so avoiding the sun isn’t going to work.

There is arginine in COUNTLESS foods most people eat every day, so good luck with that one.

And I’m pretty sure nobody gets their period or gets sick on purpose…

So really, good luck avoiding all those triggers.

Now of course, not everybody is susceptible to the same cold sore triggers. For some, it may be alcohol. For others, something else.

And to figure out what your cold sore triggers are, people often tell you to keep a diary of everything you ate and everything you did, and after a while you should be able to find patterns that will reveal what your specific triggers are.

That… sounds like a lot of work. Sounds tedious and like it may take years before you have enough data to pull reliable conclusions. Do you want to wait years before knowing how to prevent your cold sores?

I sure don’t.

So what can you do to NOT trigger a cold sore?

After doing a lot of research into what activates the biochemical pathway responsible for signaling the herpes virus to wake up, I formulated an alternate hypothesis.

What if it all boiled down to the same thing?

What if all those different triggers eventually cause the same singular event to happen in your body that activates said biochemical pathway and, in turn, reawakens the herpes virus?

Well, it turns out that there is really only one thing, one “event” that activates the biochemical pathway responsible for waking up the herpes virus. And all those triggers you read about lead to this same “event” in one way or the other.

Knowing this makes preventing cold sores by avoiding your triggers infinitely easier.

Because instead of having to avoid a bunch of different things like avoiding sunlight, not drinking alcohol, not eating arginine, not getting sick, etc, all you have to do is focus on stopping this one “event” from happening.

Once you know how to do that, cold sore prevention becomes easy, simple, and obvious.

if you want to learn how to prevent cold sores from coming back all the time, make sure to sign up and read the free first chapter of the Cold Sore Control cold sore prevention guide.

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