If you are looking into what you can find over the counter to help clear up that cold sore, you will likely come across many recommendations for Lysine.
But just what does Lysine do for cold sores, how effective is it, how much should you take, and can you use it along with other anti-viral medications?
In this article, we will cover the basics of taking Lysine for cold sores and help you get some answers.
Also Read: How to get rid of Cold Sores: 8 tips
Also Read: How to prevent Cold Sores 9 ways
Lysine is an amino acid, also known as a building block of proteins.
You may also see Lysine written as L-Lysine, these are both referring to the same thing and the “L” does not mean it is any different.
The human body does not make Lysine, so you need to get it through food or in supplement form.
Lysine is found in meat, dairy, eggs, and soybeans.
Taking Lysine by mouth may have benefits in reducing the recurrences of cold sores and lessening the severity and healing time of cold sores.
There may even be benefits of increased healing speed by applying Lysine based medications topically in ointment form.
The mechanism behind how Lysine helps with cold sores is thought to be due to its ability to block Arginine, which the herpes virus uses to replicate.
Lysine may also help support the immune system to better combat viral infections.
Most studies back up the benefits of supplementing with lysine for cold sore breakouts.
One older questionnaire study enrolled 1543 participants with either herpes labialis (cold sores) or genital herpes and had some of them take Lysine supplements. The participants that took the Lysine supplement reported a shorter healing time than the group that did not take Lysine, and 88% considered Lysine an effective treatment for herpes.
A placebo-controlled study had 27 patients with herpes take 1,000mg Lysine 3 times daily for 6 months, and had 25 herpes patients take a placebo 3 times daily. At the end of the 6 months, the group taking Lysine had an average of 2.4 fewer outbreaks, shorter healing times, and less severe symptoms than the placebo group.
However, some studies, like this 1984 study by DiGiovanna, did not find any benefits of Lysine supplementation compared to placebo. But, this could be due to the dosing being much lower than some of the other studies at only 400mg three times daily.
According to the Natural Medicines supplement database, they recommend the following dosages for cold sore prevention and treatment:
Cold Sore Prevention:
Cold Sore Treatment:
Lysine is normally well tolerated at recommended dosages, but higher dosages may have more risks of the following side effects.
The most common side effects of Lysine supplementation are diarrhea, cramps, abdominal pain, and nausea.
Sometimes other more serious issues may occur including kidney problems or gallstones.
If you are prone to kidney or gallstone issues, consult with your doctor before starting Lysine supplementation.
But, be sure to always speak with your doctor when adding supplements to your regimen.
If your cold sore breakouts are frequent and intense, you may benefit from speaking with a doctor about prescription anti-viral medications like Valacyclovir (generic Valtrex).