Q. I get cold sores occasionally, and for years have taken L-lysine tablets as soon as I feel one coming on. I continue to take several tablets a day for a few days until all signs of a cold sore are gone. It works like a charm!

A. Many readers agree with you. As far as we can tell, L-lysine has few side effects.

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  1. Ambs

    Sounds so gross, but in 5th grade my friend said she would dry them out with acetone or nail polish remover. Since I would get one almost 6 times a year, this is what I would use. It stings, but goes away. As an adult I use an rx from my doctor, Acyclovir, and it works great. When I use this, it also reduces the frequency of breakouts.

  2. CRB

    This sounds gross also. An old coworker told me her grandmother would use their earwax to get rid of their cold sores when they were kids. I attempted but it seemed the few times I’ve had then since that advice was giving, no wax in my ears?

  3. John
    Ypsilanti, MI

    I just got rid of a cold sore in one day with a combination of peppermint essential oil, eucalyptus oil and coconut oil. Peppermint oil alone may kill the virus or limit its infectability, but I’ve found that eucalyptus oil on the site helps as well. None of them stung and my lip is now healing. I got rid of about three large cold sores with one application of peppermint oil in the past (very quickly–started healing overnight). There is medical research for this approach (feel free to look in PubMed).

  4. lea

    I have also had cold sores since I was a young child. Parents with cold sores using ChapStick or other seemingly innocent items getting shared with their kids is usually how young children come in contact with the virus at such an early age. I used to get huge nickel sized blisters on the edges of my lips, especially when it got hot or I was stressed out from school, at least 4-7 times a year with almost no time to heal between.

    Now, as an adult, I have tried a lot of ‘home remedies’ and I can tell you the l-lysine regimen, paired with the tea bags or bicarbonate soda paste are winners in my book. I love the l-lysine and in my personal opinion as a larger woman I can take up to 8-10,000mg a day and only suffer mild stomach ache for a minute or two, taking the large pills may seem like a chore, but its well worth it. Look for walgreens or CVS pharmacy discounts, sometimes those 10$ bottles are buy one get one, which is awesome for people like me that take them regularly. One a day, then blast that nasty sore within 2 days with l-lysine. It does get better, treatment may be needed if they are severe, otherwise good luck!

  5. MJ

    My mother and ex-husband used to get cold sores at certain times. I finally made the connection between sunlight and the cold sores.
    It would happen like this – after a few winter months of staying indoors, we would all go out and play golf for several hours in the Texas sun. Invariably, they would both get bad cold sores the next day. Finally, I made the connection! After that, they always used a “chapstick” with sunblock whenever we went out to play golf (or whatever outdoor activity) and they stopped getting the cold sores. If they forgot, voila, the next day cold sores!

  6. Tom
    Las vegas, NV

    Lysine is definitely the way to go. Although everyone’s body is different.

    Here are some tips that I myself use.

    Sometimes when the cold sore is already in stage 1 and all hands are on deck to get rid of it. This is what I do.

    Rubbing alcohol on a napkin and place it in the sore for intervals of 30 seconds.
    Then grab a cup of fresh milk and use a napkin to soak some milk and put that on the sore for intervals of 30 seconds.
    In the meantime I prepare a protein shake with milk. protein shakes already come loaded with about 3-5000 mgs of Lysine.

    Rest for a while and then do a second round of alcohol and milk applications.

    I usually end up drinking about 2-3 protein shakes a day just in case.

    Also note everybody is different I am a 200 pound male, perhaps if you are smaller female you should take a smaller serving of the protein shake who knows.

    But those are my steps in defeating cold sores.

    Hope it helps.

  7. Annie

    Baking soda! Blowing bubbles in warm water with baking soda does the trick. It dries it out and stops the pain. Works like a charm.

  8. Ashley S.

    I have found that if left untreated cold sores can also manifest themselves as sores and cracks at the corners of the mouth in what must be an associated complaint, Angular Cheilitis. A very strong temptation is to lick the lips but of course, popular misconception that this assists the healing and alleviates pain is incorrect as it will only serve to make the problem worse. Enjoyed your posts thank you.
    Regards, Ash

  9. LCF

    Ever since I was very young child, my Mom would apply spirits of camphor on any beginning eruption of a cold sore that I or my siblings had. She did this 3-4 times a day and the next day, it was gone. As for canker sores inside the mouth, chewing one or two tablets of lactaid pills eliminates the problem overnight.

  10. CB

    Since i remember this i used to have cold sores in grade 2, every-time i caught a cold. My mom used to apply Pomegranate syrup on my sore (She knew this from my aunt who lives in Cyprus). It was applied 3-4 times in a day, my lips looked like dried blood !! The second day my sore was almost gone it didn’t even appear cause it was so small! Till today i use Pomegranate syrup when i have these annoying cold sore. It works miracles. Pomegranate has many useful ingredients including Anti oxidants its really effective! It works miracles with me, i hope it does the same to you, because i know how annoying it is to have a cold sore on the lips (What a turn off!!)

  11. Bess

    My husband and daughter get cold sores, and used to use Campho-phenique. It is diluted camphor though, so now at the first tingle they apply pure White Camphor essential oil. Several applications a day with a Q-tip usually prevent the cold sores from erupting at all!
    If they don’t get started soon enough or the sore breaks open anyway (rare), they alternate application the White Camphor essential oil with Lavender essential oil. The Lavender heals as the Camphor reduces inflammation.
    Each oil is about $5 for a 1/2 ounce bottle, but with the two of them using drops of oil on a cotton swab (no touching the bottle dropper!), the $10 investment last well over a year. We like Aura Cacia brand. Whatever brand you choose, make sure there are no “carrier” oils so you get only the pure essential oil.

  12. KNS

    Actually I know the absolute best to cure a cold sore coming on. I have had them since I was in 5th grade and just found out yesterday and it has practically killed my cold sore in 48 hrs – it didn’t even break skin!
    Ice it. As much as humanly possible. The virus cannot live in cold. The ice should be directly applied to the cold sore. I do it as much as 10 times a day.
    Ice combined with a max of 5000 mg of L-lysine a day will kill it in its tracks.
    Try it.

  13. David N.

    Over the years I would occasionally bump the inside of my mouth (just below the gum line) when getting a little too aggressive while brushing my teeth. I would almost always get a canker sore where the damaged tissue was. I learned from my mother the many uses of Campho-Phenique. I would get a q-tip that was dipped in the C-P and then dab it on the sore just one time. The discomfort would be gone within 8-12 hours and it would usually be fully healed in two days.

  14. Diane

    I don’t get cold sores, but I tend to bite the inside of my mouth a lot, and these bites become inflamed and turn into painful white canker sores that last up to two weeks, which makes eating a misery. I was told to take L-lysine every day, which I do, and now when I bite the inside of my mouth the sores heal within a few days. It has made my life so much better! After a bite, or when a canker sore is coming on, I also make sure to keep my mouth very clean after every meal and before bedtime by brushing my teeth and swishing with Listerine. This “double punch” of l-lysine and Listerine has been a Godsend to me.

  15. Bonnie

    I also take L-lysine with great success. A doctor once told me there was a relation between peanuts & cashew nuts and cold sores, once I eliminated both from my diet, I had fewer cold sores.
    Unfortunately I don’t remember what in those nuts causes the outbreak. It took awhile for me to get used to almond butter as a substitute for peanut butter, but eventually I did.

    • Aoife

      I read its the arginine in nuts and chocolate that exacerbates coldsores and by taking lysine it blocks the arginine receptors? Something like that anyway!

  16. ruth

    I too suffer from cold sores. My MD told me of L-Lysine. I took it only when I felt the blisters coming on till they were scabbed over and gone. Last fall I started getting them almost as fast as the previous ones would heal. I started taking the tabs daily and since Jan. NO outbreak of blisters!! The scars on my nose, lips and upper lip area are finally starting to fade. So long as I can get this med, I will take it!!

  17. cls

    I have been taking 500 mg of Lysine daily for about 30 yrs. I cannot take Lysine to tamp down flare-ups as some folks do, but I have to adhere to a daily regimen of intake. If my routine is broken for 2 or more weeks, and I forget to take the daily dose like preventive maintenance, I will have 4-5 huge, swollen blisters on my lips that sometimes leave scars. So long as I adhere to Lysine intake regularly, I have no problems.

  18. grampi

    This may sound gross, but I put my own urine on them, & they are gone the next day! An old-timer, when I was a child, told me about this (55-58 years ago).

    • Jenn

      I don’t know if I could do it, but my Latvian friend swears by this too – her grandmother told her about it!

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