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Pure Lysine

Vita-Flex Nutrition — Item #11711
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Economical form of lysine

  • 9,099 mg of pure lysine
  • Lysine must be provided in your horse's diet because the body cannot make it on its own
Lysine is the protein component most often lacking in horses' diets. Pure Lysine provides a pure and economical form of this nutrient.

Learn More about Pure Lysine

View our Muscle Supplement Comparison Chart


Guaranteed Analysis:
(Maintenance Dose = 3 scoops (12 g) daily)
Ingredient Per Serving Per Pound
Lysine 9,099 mg 78.8%
Ingredient:: L-Lysine monohydrochloride.


Instructions for Use:
Enclosed scoop holds 4 grams.
For foals and weanlings up to one year: feed 1 scoop (4 grams) per day.
For maintenance of mature horses: Feed 1 to 3 scoops (4-12 grams) daily.
For broodmares, horses in heavy training or competition: Feed 2 to 3 scoops (8-12 grams) daily.

Clinical Research

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    out of 5
    92% of customers would recommend this product to a friend!
    Tell us what you think!

    The reviews provided on this website represent the experience of the individual posting the review. We do not adopt, edit, or endorse any of the submissions posted within the reviews section. Rather, the reviews are part of an online community of animal owners that desire to share their particular experience with other individuals. These reviews are not a substitute for discussing the health of your animal with a veterinarian.

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    Pure Lysine is rated 4.6 out of 5 by 101.
    Rated 4 out of 5 by from Seems to work My gelding does seem to be gaining lean muscle very well (but not the bulk I was hoping for-and that he is bred for) He eats it just fine. Its definitely a good value!
    Date published: 2012-04-20
    Rated 5 out of 5 by from Great Natural Way To Fill Out!! I noticed results around the second week. My 7 year old show gelding was really filling out over his withers extending into his back, I was getting shape over the top line and even getting more grooves down his rear quarter. I love this supplement. He doesn't act hot or wound up, just is putting on shape in the right places, from food he's already eating. love this supplement, he will never be without it, from this point on.
    Date published: 2012-04-19
    Rated 5 out of 5 by from 100% pure lysine Living in a lysine deficient area I find this to be very inexpensive and very palatable for my horses. Also seems to be a calming supplement,
    Date published: 2012-03-18
    Rated 3 out of 5 by from Ahh if only I really wanted my mare to eat this -- she was going into heavy work for the first time and I wanted to have all the amino acids covered, but she refused to eat it. She'd pick her pan up and dump all the grain out :( and when I mixed applesauce in with all of it she outright refused it. Alas, on to the next challenge!
    Date published: 2012-03-08
    Rated 4 out of 5 by from Improves Hoof Health My Appy/Draft cross (@13 yrs.) has been barefoot w/ a natural trim since I've owned him (2 yrs.+) and has done well. We participate in a variety of activities. However, he suffers a laminitic type reaction to vaccinations w/ accompanying tenderness and loss of concavity. The 2nd time this happened, my trimmer suggested supplementing with l-lysine (along w/ milk thistle for detox) and he recovered much faster. His overall hoof (incl. frog) quality is better also. I check his feet daily & rasp him weekly between trims, so I am very aware of any changes to his feet. He also seems to be feeling and moving better in general. I have also seen similar improvement in 2 other horses on the farm who were much worse off. All 3 are easy keepers and so far this has proved to be a simple and economical way to supply them with a vital nutrient w/o compromising their health in other ways.
    Date published: 2012-02-21
    Rated 5 out of 5 by from Worth the money! I have a 3 1/2 year old 16.1hh Hackney Horse filly, who while I was recovering from an injury left unridden and lost her muscle mass. She has been doing drastic growth spurts and so without being ridden became rather straggly. I wanted to find something that would encourage the muscle w/o it being unnatural. I already knew she was healthy, however I also knew that her body was expending most of its energy on her bones and tendons. I tried this product because it was relatively inexpensive and would appear to be something that could help a youngster. Within a week of her going on it there was a large difference. Hollow haunches filled out, her topline came back and she was very happy. For this price she can stay on it. I then put my mare on it and the same thing happened within a week. This product is worth the money!
    Date published: 2012-01-29
    Rated 5 out of 5 by from Fantastic product - great price! We bought an APHA gelding (QH stock type crossed with Jockey Club mare) and he was about 300 pounds under weight. After struggling with getting him to add weight without making him hot, some research brought me to this product. Pure Lysine has made all the difference. He's gained and held weight and muscle tone that I never thought possible. My Dad and Uncle commented this Fall that he's filled out more than they thought possible given his frame and thoroughbred blood. Even the farrier commented a couple of weeks ago about his condition. (This is all after about six months on Pure Lysine.) So, due to success with Dutch, we put my 30 year old gelding on it this winter since an illness caused him to lose weight just before Thanksgiving, which is not good for an aged horse that has Cushings and facing a WI winter. Well, he's actually gaining his weight back and is happy too - he ran and bucked along the paddock fence with a youngster while riding by a couple of weeks ago. Great bang for the buck! =)
    Date published: 2012-01-25
    Rated 5 out of 5 by from Licks the bowl clean I started this product along with weigh gain and my mare loves it, this doesn't even have to be mixed in grain. She will eat it straight out of her dish.
    Date published: 2011-12-02
    Rated 5 out of 5 by from Great Product !! I have to say im very pleased with product, had an orphan APHA (thoroughbred/paint) colt who got so underweight after his dam passed away from colic when he was 1 1/2 old, no matter what he was fed he just would not put weight on or even grow (he probably ate more then any horse in the entire barn). Got so bad that a random passerbyer had actually called animal control on him. Had everything from the vet so it came to be nothing, but thats when i started to look for something that would be a good for him other then his grow colt supplement and calf manna that would be safe for a growing foal. Started this product when he was about 3 1/2 months old and after about 3 weeks started seeing a change he started filling out and not only putting on the weight but keeping it as well as growing. He's now 7 months old and over 13hh and is still maintaining his weight and doesn't have a rib to show, might actually reach the full potiental he was born to grow with both his sire and dam being 17hh. He now is only on Pure Lysine and Grow Colt and is holding out great. Would Definately Recommend this product, it worked wonders for me.
    Date published: 2011-11-27
    Rated 5 out of 5 by from Quality Product I am very pleased with the Lysine that I purchased through Smart Pack. I researched other Lysine Supplements and SmartPack beat the others in quality and price. I have been feeding the Lysine to a 23 year old QH gelding and 34 Welsh Mare and in less that 3 weeks there was a noticable improvement of their muscling over their topline!
    Date published: 2011-11-19
    Rated 5 out of 5 by from Muscle! I can't believe how much muscle my Friesian has put on since starting on this product! He seems so much taller to me with the improvement in his topline. Very happy! Great result for little $'s.
    Date published: 2011-11-16
    Rated 5 out of 5 by from A Product That Works Wonders! I have a 17'2 Oldenburg Warmblood jumper athlete. When I first got him he was neglected and needed to put on weight and get back into shape. I had him on a special program with lots of supplements to help him gain weight and an exercise routine for the muscle development. When he only had about 200 more pounds to look like a 4 foot jumper, I really wanted him to have some flashy Warmblood muscle definition. Now, my horse was being worked almost every day during this weight gaining process. But Pure Lysine REALLY made a difference! In about 2 weeks I noticed muscle definition in places I never thought would get there for a while with time and exercise. He was feeling great and wanted to exercise for over an hour! It also helped with muscle soreness after a long ride or jumping lesson. I am thrilled with this product and will use it for a lifetime! I started out with 3 scoops of the product, when my horse looks healthy I will probably cut it back to 1 scoop. I definitively recommend this product for athletic horses that want a flashy muscle definition and horses that need to put on weight without consuming to much grain and supplements. A great way to get results without having a "hot horse."
    Date published: 2011-10-14
    Rated 3 out of 5 by from Lysine not great I expected by the description given that the Lysine would promote muscle and healthy hooves. I haven't really seen any changes in the horses. They don't really like the taste either.
    Date published: 2011-10-04
    Rated 4 out of 5 by from Once you get past the smell... This product smells completely rank, but once you get past the smell, I think the results in improving your horses' coat and build are worth it.
    Date published: 2011-09-30
    Rated 5 out of 5 by from Great Choice I purchased Pure Lysine on the reccomendation of a fellow barrel racer, whos horse also had a deteriorating top line. I was told about how pure lysine had brought back the muscle and evened hid back out. I decided to try it on my mare. She was only on it for 2 months (I don't ride in the winter, so she isn't grained), and I noticed a definite change in her topline. She will definitely be on this again in April!
    Date published: 2011-08-26
    Rated 5 out of 5 by from Good product I put my horse on this as a recommendation for treating head shaking syndrome (HSS) since lysine counteracts the herpes virus. My horse is on 20g/day and eats it all (but he is not a picky eater). He has been out of work for about 1.5 months and still is in good condition, and I think this product is helping him keep his muscle tone while on "vacation". It's relatively cheap to feed which is a plus as well.
    Date published: 2011-07-05
    Rated 5 out of 5 by from Seeing Results Already Don't know how fast it really works, but it looks like my horse is already benefiting from the Lysine. I can visably see where his muscles are starting to show definition.
    Date published: 2011-07-01
    Rated 4 out of 5 by from Lysine is good for muscles My horse is about 30 years old. When I bought him, he was malnourished. Since then, I have added some supplements to his diet. Lysine is one of the supplements that I added due to the poor quality of the grass hay here in Amarillo, TX, and also, due to the fact that he is in a run instead of out on pasture. I feel that the lysine has contributed to the development of muscle in his hind end and back. His sagging spine seems to have lifted somewhat. I did not expect him to recover from this kind of deterioration. However, he is running through the arena now, and actually bucking, something I have never seen him do before. It's like he is saying, "I feel GOOD!"
    Date published: 2011-06-24
    Rated 5 out of 5 by from Excellent product My warmblood gelding is not an easy keeper, especially in the winter when I have to cut back on his grain a bit. A friend suggested trying a lysine supplement and within weeks he started maintaining weight. His coat and hooves improved as well. Come summer, he built up so much muscle he looked like a different horse than the previous year. I had alot of luck with this product and I would highly recommend it to anyone who is considering an amino acid supplement. Especially for the price, you cannot go wrong giving it a try. You will know within a month if it is helping or not!
    Date published: 2011-05-23
    Rated 2 out of 5 by from My mare would not eat it. I would not recommend it for a picky eater.
    Date published: 2011-04-13
    Rated 5 out of 5 by from Helps build more muscle mass My horses chiropractor was the one who recommended lysine for my horse. Before I started using lysine for my horse. He didn't have a lot of muscle mass and he need to gain some more weight. Now after being on lysine for 2 years. He looks great. He has nice topline and it helped him maintain his weight. It also help make his hooves much stronger.
    Date published: 2011-03-27
    Rated 5 out of 5 by from GREAT STUFF Have seen marked improvement on my TB mare's topline. Giving to my old lady AQHA and her farrier is amazed at how much better her movements and feet have improved.
    Date published: 2011-02-25
    Rated 5 out of 5 by from Wonderful Product I live near a race training track and was told by a local feed store that the trainers use lysine to keep the young horses from developing ulcers. I have a PMU who has ulcer colic, since I have used lysine I have had success. I have been giving it to my mare for 5 years and love it.
    Date published: 2011-02-17
    Rated 5 out of 5 by from Cheap Product With Good Results Bought this product to help better define my young horses muscles and fill out their top line. In the short time they've been on it I have seen a small difference in their muscle definitions. It's a cheap product that will last me a while!
    Date published: 2011-02-10
    Rated 3 out of 5 by from Undecided I have been using this product on two of my horses for about three months. One of the two horses hooves has shown much improvement but other than that I haven't noticed any other change yet. I was really wanting to see better top line and more weight gain but maybe it just takes more time.
    Date published: 2011-02-02
    Rated 5 out of 5 by from LYSINE FOR RESCUE CATS I have been buying the 4lb Bucket of Lysine for my 50 rescue cats for several years. It is in granules but if you want powder just put it in a coffee bean grinder and shake it on to individual cats food. It is used to keep them healthy and to treat them when they are sick. It is good for their mouths, respiratory illness, etc. It is a good quality product at a good price and I do price shop when taking care of as many rescue animals as I do. So I do recommend it highly.
    Date published: 2011-02-02
    Rated 5 out of 5 by from PREVENTION I bought this product as a prevention to bolster Harmony's immune system. It seems to be working.
    Date published: 2011-02-01
    Rated 5 out of 5 by from Quality Product My horse has been on this supplement for a month now and he already seems to be filling out. His coat also seems shinier. The day after I ordered this product smartpak was closed due to inclement weather, but I still received it two days after placing my order.
    Date published: 2011-01-18
    Rated 3 out of 5 by from Good Product I recently started using this product on an older horse that has lost muscle tone. He has put on wieght elsewhere, but is still showing a noticeable loss of weight in his hindquarters and I was hoping to see the Lysine claims of increased muscle mass. After 60 days of use I can see great improvement in his hooves (I am a farrier so I was looking for that), his eyes and coat seem improved, but as it is winter time, its hard to tell!! There is no improvement to muscle mass anywhere. Will continue to use for at least 6 months and review again.
    Date published: 2010-12-30
    Rated 5 out of 5 by from WOW. This stuff is simply amazing! I ride my 17 yr. old hard and some one suggested this to me as a muscle builder to help process her protein. She said that it helps swaybacks also. My 17.1 TB has always been VERY sharkfinned and I noticed her losing topline muscle. I put her on this and the muscle around her withers is filling out so nicely! She also looks like she is adding muscle on her topline. My horse really doesn't like it but and I wish it came in pellest but eventually over the course of the day it is eventually consumed. I JUST SIMPLY LOVE THIS STUFF!
    Date published: 2010-12-30
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