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Home Ask the Experts Ask the Experts L-lysine for cold sores?

L-lysine for cold sores?

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I have had cold sores (which I now know are oral herpes) since I was teenager, and average about one, maybe two, outbreaks a year. I would like to know more about prevention-specifically any dietary supplements that are recommended, like L-lysine, to prevent outbreaks. What dosage is recommended? Should this be taken daily?

While some people have reported beneficial effects from taking lysine (L-Lysine, an amino acid), it has not been clinically proven to help with herpes, and therefore we cannot recommend specific dosages. While some studies have suggested that lysine supplements can reduce the frequency of recurrences or healing time, other trials have been unable to replicate those results. Therefore, there is not sufficient information to determine how effective it may be, in addition to what the effective dosages or frequency of L-lysine may be. Any claims on its effectiveness are based strictly on anecdotal evidence.

There have been no specific nutrients proven to reduce the frequency of outbreaks. However, it is important that an individual maintain a healthy diet for many reasons.

If you are interested in treatments, there are FDA-approved medications available to both lessen the severity and duration of outbreaks. We encourage you to speak with your healthcare provider about these medications if you feel they may be an option for you.


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