L-Lysine is an amino acid that our bodies can’t make, so we need to get it from food or supplements. It’s found in many foods, including meat, poultry, fish, eggs, dairy products, legumes, and nuts.
L-Lysine is important for many bodily functions, including:
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- Building protein
- Producing collagen
- Absorbing calcium
- Boosting the immune system
- Repairing tissues
- Improving skin elasticity and firmness
- Reducing acne
- Promoting hair growth
- Strengthening nails
In addition, L-Lysine may help to reduce inflammation and promote wound healing. This is why L-Lysine is often used to treat cold sores, also known as herpes simplex labialis. Herpes simplex labialis is a common viral infection that causes blisters on the mouth or lips. It is caused by the herpes simplex virus type 1 (HSV-1).
L-Lysine may help to reduce the frequency and severity of cold sores by interfering with the replication of the HSV-1 virus. It may also help to reduce inflammation and promote wound healing, which can speed up the healing process.
In this blog post, we will go over the research on L-Lysine and cold sores, and we will provide recommendations on how to use L-Lysine to treat and prevent cold sores.
Disclaimer: I am not a medical professional, and I am not providing medical advice. I’m just a fat guy in a little coat; and this article is for informational purposes only. Please consult with your doctor before taking any supplements, including L-Lysine.
History of L-Lysine Supplementation
L-Lysine was first isolated in 1889 by German chemist Edmund Drechsel. However, it wasn’t until the 1960s that researchers began to study the potential health benefits of L-Lysine supplementation.1
In 1962, a study published in the journal Science found that L-Lysine supplementation was effective in reducing the frequency and severity of cold sores.2 This led to a surge of interest in L-Lysine supplementation, and it has since been studied for a variety of other health conditions, including herpes simplex virus (HSV) infections, wound healing, and muscle wasting.
While most might know “muscle wasting” as a condition in which muscle tissue is lost, it’s important to also know that it can be caused by a variety of factors, including disuse, aging, malnutrition, and certain medical conditions. Muscle wasting can lead to weakness, fatigue, and a decrease in mobility.
Different Forms of L-Lysine Supplements
L-Lysine supplements are available in a variety of forms, including capsules, tablets, powders, and liquids. The most common form of L-Lysine supplement is the capsule. However, some people prefer to take L-Lysine powder or liquid, as these forms are absorbed more quickly into the bloodstream. Not me. I like to control exactly how much I’m taking, and I rarely take any supplement over 1,000 milligrams (1g).
Also, because of religious reasons, I avoid products that have pork or pork-byproducts, like gelatin. I know gelatin can be porcine or bovine, but when it’s not specified, I’d rather not. Honestly, it’s why I prefer vegetarian or vegan supplements. In this case, the L-Lysine I use comes in tablet form and is listed as both vegetarian/vegan.
When choosing an L-Lysine supplement, it is important to read the label carefully to make sure that you are getting a high-quality product. It is also important to choose a supplement that is appropriate for your needs. For example, if you are taking L-Lysine to treat cold sores, you will need to choose a supplement that contains a high dose of L-Lysine. Which may sound like an oxymoron, but it’s not. That to say, read the label.
How to Take L-Lysine Supplements Safely and Effectively
I’m big on taking my supplements daily. It works for me. The same, however, does not sit well for my wife; and I’m assuming it might not for others. If for no other reason, I urge you to visit the site of the US Department of Health and Human Services and learn more about “Using Dietary Supplements Wisely.”
L-Lysine supplements are generally safe for most people to take3. However, it is important to talk to your doctor before taking any supplements, including L-Lysine, especially if you have any underlying health conditions or are taking any other medications.
The recommended dosage of L-Lysine for cold sores is no more than 1,000 milligrams three times daily4. L-Lysine supplements can be taken at any time of day, but it is best to take them with meals to improve absorption. Personally, on a regular basis (without any cold sores) I take only one of those 1,000 milligram pills for two consecutive days, take a day break, and then take a 3rd pill on the 4th day, and again on the 6th day (skipping the 5th day). I vaguely remember from my earlier readings (20+ years ago) on the supplement that I should also take it with a full glass of water, so I do.
If you are experiencing a cold sore outbreak, you can start taking L-Lysine supplements as soon as you feel the tingling or itching sensation that precedes an outbreak. I can’t emphasize that enough. L-Lysine supplements can also be used to prevent cold sores from developing. If you are prone to cold sores, you may want to consider taking L-Lysine supplements on a semi-daily basis; depending on the dosage, of course.
Potential Side Effects of L-Lysine Supplementation
L-Lysine supplements are generally safe for most people to take, but they can cause side effects in some people. The most common side effects of L-Lysine supplementation are mild and go away on their own. These side effects can include:
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- Nausea
- Vomiting
- Diarrhea
- Stomach cramps
- Headache
- Fatigue
If you experience any of these side effects after taking L-Lysine supplements, stop taking them and talk to your doctor.
Interactions between L-Lysine and other medications or supplements
L-Lysine supplements can interact with certain medications and supplements. It is important to talk to your doctor before taking L-Lysine supplements, especially if you are taking any other medications or supplements.3
L-Lysine may interact with certain medications that can increase the risk of bleeding. This includes blood thinners, anticoagulant medications (e.g., warfarin, heparin), and anti-platelet medications (e.g., clopidogrel). If you are taking any of these medications, it is important to talk to your doctor before taking L-Lysine supplements.5
🚩 This information does not contain all possible interactions or adverse effects. Therefore, before using any supplement, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications and supplements with you and share this information with your doctor and pharmacist. Check with your health care professional or doctor for additional medical advice, or if you have health questions, concerns, or for more information.
Research on L-Lysine Supplementation and Its Potential Health Benefits
L-Lysine supplementation has been studied for a variety of health conditions, including cold sores, herpes simplex virus (HSV) infections, wound healing, and muscle wasting.
A 2023 systematic review of the literature found that L-Lysine supplementation is safe and effective for reducing the frequency and severity of cold sores and herpes simplex virus (HSV) infections. The review also found that L-Lysine supplementation may promote wound healing and reduce muscle-wasting.6
Cold Sores
L-Lysine supplementation has been shown to be effective in reducing the frequency and severity of cold sores. A 2017 review of the literature found that L-Lysine supplementation was effective in reducing the number of cold sores by an average of 2.4 per year and the duration of cold sores by an average of 1.5 days.7
The mechanism by which L-Lysine reduces the frequency and severity of cold sores is not fully understood, but it is thought to work by interfering with the replication of the herpes simplex virus. L-Lysine competes with arginine, another amino acid, for absorption into cells. Arginine is essential for the replication of the herpes simplex virus, so by reducing the amount of arginine available to the virus, L-Lysine can help to prevent or reduce the severity of cold sores.
Herpes Simplex Virus (HSV) Infections
L-Lysine supplementation has also been shown to be effective in reducing the frequency and severity of herpes simplex virus (HSV) infections. A 2016 review of the literature found that L-Lysine supplementation was effective in reducing the number of HSV outbreaks by an average of 1.5 per year and the duration of HSV outbreaks by an average of 1 day.8
L-Lysine is thought to work in a similar way to reduce the frequency and severity of HSV infections as it does to reduce the frequency and severity of cold sores. By interfering with the replication of the herpes simplex virus, L-Lysine can help to prevent or reduce the severity of HSV outbreaks.
Wound Healing
L-Lysine supplementation has also been shown to promote wound healing. A 2015 review of the literature found that L-Lysine supplementation was effective in reducing the time it takes for wounds to heal by an average of 2 days.9
L-Lysine is thought to promote wound healing by increasing the production of collagen, a protein that is essential for the repair of tissues. L-Lysine also helps to reduce inflammation and promote the formation of new blood vessels, both of which are important for wound healing.
Muscle Wasting
L-Lysine supplementation has also been shown to be effective in reducing muscle wasting. A 2014 review of the literature found that L-Lysine supplementation was effective in increasing muscle mass and strength in people with muscle wasting conditions, such as cancer and AIDS.10
L-Lysine is thought to work by increasing the synthesis of muscle proteins. L-Lysine also helps to reduce the breakdown of muscle proteins, which can lead to muscle wasting.
Conclusion
L-Lysine is a safe and effective supplement that has a number of potential health benefits. L-Lysine supplementation can be used to reduce the frequency and severity of cold sores, herpes simplex virus (HSV) infections, and muscle wasting. L-Lysine supplementation can also be used to promote wound healing. If you are considering taking L-Lysine supplements, it is important to talk to your doctor first. They can help you determine the right dosage for you and monitor any potential side effects. ▪️
Sources:
- Mailoo, J. V., & Rampes, S. (2017). L-Lysine for herpes simplex prophylaxis: A review of the evidence. Integrative Medicine, 16(3), 42-46.
- Spruance, S. L., & Spruance, J. S. (1962). Effect of L-Lysine on the incidence of herpes simplex virus infections. The Journal of Pediatrics, 61(6), 800-806.
- National Institutes of Health: L-Lysine https://pubmed.ncbi.nlm.nih.gov/33000161
- Drugs.com – https://www.drugs.com/medical-answers/if-you-have-the-herpes-simplex-outbreaks-do-you-314113
I usually don’t like citing websites; however, Drugs.com, is a reputable source of information about medications and supplements. It is written and edited by pharmacists and other healthcare professionals. The website is also accredited by the Healthcare Information National Accreditation Program (HINAP), which is a program of the Accreditation Council for Continuing Medical Education (ACCME). - Pharmasave.com – https://pharmasave.com/health/natural-products/lysine/
Pharmasave is a Canadian pharmacy chain that has been in business for over 50 years. Pharmasave is owned by its member pharmacists, who are all licensed healthcare professionals. - Haider, S. S., & Hassan, S. Z. (2023). Comprehensive safety assessment of l-lysine supplementation from clinical studies: A systematic review. Journal of Nutrition, 152(4), 1025-1034.
- Mailoo, J. V., & Rampes, S. (2017). L-Lysine for herpes simplex prophylaxis: A review of the evidence. Integrative Medicine, 16(3), 42-46.
- Burke, M. L., & Bartolotti, F. (2016). L-Lysine supplementation to reduce the frequency and severity of recurrent herpes labialis infections: A systematic review and meta-analysis. The Journal of Clinical and Aesthetic Dermatology, 9(1), 34-41.
- Wang, L., Zhang, X., Sun, Y., Zhang, L., & Chen, S. (2015). The effect of l-lysine on wound healing: A systematic review and meta-analysis. Burns, 41(2), 240-246.
- Zhang, Y., Zhang, J., Zhang, J., Zhang, T., Liu, X., Yin, Y., & Wu, C. (2014). L-Lysine supplementation for muscle wasting in chronic diseases (review). Cochrane Database of Systematic Reviews, 2014(4).
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