7 Best Lysine Supplements (2024) Reviewed and Compared

Never miss a glorious update - click here!

Lysine is an essential amino acid that’s required for countless bodily functions.

As a supplement, it’s most common used for preventing colds as well as helping with herpes outbreaks.

Look, what can we say, RFS readers definitely fuck, and herpes may be an unfortunate cost for some of us out there.

(Of course, you should still practice safe sex. This is NOT a substitute for safe practices. This is not medical advice and we don’t pretend to be doctors.)

While the research on these benefits is promising, it’s definitely incomplete. But since lysine is a safe, inexpensive ingredient, it comes with very little risk.

Low risk with medium-high benefit is exactly the kind of trade-off we look for in a supplement.

What Is Lysine?

Lysine is an amino acid, which are the building blocks of protein. In particular, it’s one of the essential amino acids, which means the body doesn’t produce it on its own, so we have to get it from food.

The Benefits of Supplementing with Lysine

Because it’s an amino acid, it plays a role in a whole bunch of bodily functions and protein creation. So it has a range of benefits.

Reduces the frequency and severity of herpes outbreaks. Lysine supplements may help to reduce the frequency and severity of herpes outbreaks. One study found that taking a lysine supplement reduced the number of outbreaks by nearly 60%. As for a dose, studies show that 2g per day is effective.

Reducing soreness and DOMS (delayed-onset muscle soreness): The bottom line is if you’re lacking essential amino acids like lysine, your performance and recovery will suffer. In this respect though, I’d recommend simply eating more protein, or not training like a moron.

Boosts immune function: Lysine supplements may help to boost immune function. One study found that taking a lysine supplement increased levels of antibodies, which are proteins that fight off infections.

Reduces anxiety: Lysine supplements may help to reduce anxiety. A study found that taking a lysine supplement improved symptoms of anxiety in people with anxiety disorders.

Supports collagen synthesis. We need collagen for everything from hair health to joint health. Lysine is an essential amino acid for our body to create it on its own. Along these lines, it can support bone health and wound healing. It may even help protect you from osteoporosis, according to some research.

Building block for other aminos. Lysine is important for carnitine generation, for example.

How to Choose the Best Lysine Supplement for You

When choosing a lysine supplement, there are several things you should keep in mind.


First, make sure that the supplement is GMP-certified. GMP stands for “good manufacturing practices.” This certification means that the supplement is made in a facility that follows strict quality control standards.

If it isn’t, run for the hills. What’s on the label might not be what’s actually in the product.


Lysine is available in capsules, tablets, powders, and liquids. This factor is mostly a matter of personal preference. Capsules and tablets are the most convenient, while powders and liquids are typically cheaper.


Most supplements have 500-1000 mg of lysine per serving. This is a safe and effective dose for most people, but you may need more or less depending on your individual needs. If you’re taking it for herpes, 2 grams per day seems to be the effective dosage.


Liquids and powder are usually cheaper than capsules. But lysine capsules are still inexpensive, and it’s hard to beat the convenience of capsules.

Talk to Your Doctor

Lastly, consult with a healthcare provider before taking any supplement, especially if you have a medical condition or are taking medication.

*Note: We do have affiliate links throughout this article, which means we receive a commission if you purchase from any of our links. This supports our mission to bring complicated health and fitness info in an entertaining package. And it keeps us from putting up annoying things like banner ads. Those suck.

1) NOW Foods L-Lysine Supplement 1000mg Tablets (Best Overall)

Check Lowest Price

Oftentimes with supplements, your best choice is the simplest. That’s the case with this NOW Foods products, and to be honest, most of their products. It contains lysine and nothing else, at a value that you won’t find unless you go with a bulk product.

Now Foods L-Lysine 1000 mg tablets are a cGMP-certified, vegetarian supplement. They are available in 100- or 250-tablet sizes.

Serving size: 1 capsule

Servings per container: 100 / 250

Price: $7.49 / $16.29

Look, for just 7 bucks you can get full clinical doses from one of the most trusted supplement brands out there.

Honestly, it’s kind of a no-brainer to start with NOW Foods L-Lysine.

It’s non-GMO, gluten-free, dairy-free, soy-free, and suitable for vegans.

2) Quantum Health Super Lysine

Quantum Health, Super Lysine Immune Support

Quantum Health Super Lysine includes other ingredients besides just lysine to support your immune system. Notably, it has vitamin C, echinacea, and licorice, all of which are interesting ingredients for immune health. 

If you’re taking lysine specifically for immune support, this is a great option.

Serving size: 1 capsule

Servings per container: 90 / 180

Price: $9.34 / $17.22

Check Lowest Price

3) Pure Bulk Supplements L-Lysine HCl (Best Bulk)

best bulk l-lysine powder

Check Lowest Price

Pure Bulk Supplements always bring the best combination of value and quality out there. You can get a whopping 500 grams of l-lysine for just $13.50.

Now, the upshot to that value is it comes in powder form (they also have capsules). The powder doesn’t have a strong flavor, so it’s easy to mix in smoothies, juices, or pretty much any other beverage.

However, if you prefer the convenience of capsules, then probably look elsewhere.

4) Thorne L-Lysine 500 mg Capsules

Check Lowest Price

This is also a simple product from a reputable company. Thorne is one of the most well-trusted and reputable supplement companies out there.  Each capsule has 500 mg of lysine. They’re also free of gluten, dairy, soy, and nuts.

Serving size: 1 capsule

Servings per container: 60

Price: $11.00

5) Life Extension L-Lysine 620 mg capsules

life extension l-lysine

Check Lowest Price

If you’re looking for a lower-dose supplement, Life Extension L-Lysine capsules are a great option. These GMP-certified capsules contain 620 mg of lysine per serving.

Serving size: 1 capsule

Servings per container: 100

Price: $7.33

6) Solgar L-Lysine 500 mg Tablets

Solgar L-Lysine

Check Lowest Price


The next supplement on our list is Solgar L-Lysine 500 mg capsules. These GMP-certified capsules are made from non-lactose ingredients and are suitable for vegetarians. They also contain no artificial flavors, colors, or sweeteners.

Serving size: 1 capsule

Servings per container: 100 / 250

Price: $11.99 / $23.00

7) Nature’s Bounty L-Lysine 1000 mg Capsules

Check Lowest Price


Nature’s Bounty L-Lysine 1000 mg tablets is another great GMP-certified supplement. These tablets are made from toxic-free, FDA-approved ingredients. This company contracts out to big pharmacies, like CVS, so they’re a trusted brand.

Serving size: 1 tablet

Servings per container: 60

Price: $7.49

How We Ranked the Best Lysine Supplements

The reality is lysine supplements are all super simple. We’re not talking about pre-workouts where there could be all kinds of different ingredients. So it’s much more about safety, quality, and cost. We looked at the following criteria.

  • The type of supplement (capsule, tablet, powder, or liquid)
  • The dosage (500 mg – 1000 mg per serving)
  • The price
  • Reputation of the company. The supplement industry is full of crap. So we gave a boost to companies with a proven track record of safety and efficacy.
  • The ingredients (vega, gluten-free, etc.)
  • Certifications (GMP, FDA, etc.)

Pretty simple stuff. Don’t try to overcomplicate it, or let companies convince you that it’s complicated.


What Are The Side Effects of Taking Lysine

Lysine supplements are generally safe and well-tolerated. However, they may cause some side effects, such as:

  • Upset stomach: Lysine supplements may cause an upset stomach. If this occurs, take the supplement with food or milk.
  • Diarrhea: Lysine supplements may cause diarrhea. If this happens, reduce the dosage or frequency of supplementation.
  • Headache: Lysine supplements may cause headaches in some people. If this is the case for you, try taking a lower dose.

What is lysine?

Lysine is an essential amino acid that our bodies need to perform various functions. It is found in many foods, such as meat, fish, beans, and dairy products.

What are the benefits of taking a lysine supplement?

There are many potential benefits of taking a lysine supplement. Some people take it to help with cold sores or herpes outbreaks. Others take it for general health purposes, such as to improve calcium absorption or to boost immunity.

How much lysine should I take?

While products come in 500mg-1000 mg doses, many studies suggest closer to 2g.

Can I get lysine from an essential amino acid supplement?

If you’re looking for a supplement that provides you with all of the essential amino acids, then an EAA supplement is a great option.

Is it safe to take a lysine supplement?

Yes, lysine supplements are generally safe for most people. But of course talk to your healthcare provider before taking any supplement especially if you have a medical condition or are taking medication.

Does lysine help with herpes outbreaks?

The research on lysine and herpes is mixed. However, in combination with a low arginine diet, lysine supplementation does seem to treat herpes simplex virus (HSV) in some cases.)

Can I take a lysine supplement if I’m pregnant or breastfeeding?

This is a question for your doctor, not some stranger on the internet.

About the Author

David William Rosales is a writer and strength coach. He's the head trainer and editor at Roman Fitness Systems. In addition to helping run RFS, he's also the head editor for, the official website of the Strength and Conditioning Association of Professional Hockey. You can also check out his Instagram, he's pretty easy on the eyes.

Leave a Comment