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Senior Flex
Med-Vet Pharmaceuticals (MVP) — Item #11817
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Targeted support for senior joint health

  • 5,000 mg of glucosamine, 500 mg of chondroitin sulfate, 3,000 mg of MSM, & yucca for healthy joints
  • Includes vitamin A & vitamin E for antioxidant support, plus probiotics for healthy digestion
Senior Flex is a unique combination of joint, digestive, and antioxidant support for the senior horse. Provides 5,000 mg of glucosamine, 500 mg of chondroitin sulfate, 3,000 mg of MSM, 5,500 mg of yucca, 1,200 mg of Ester-C, 15,000 IUs of vitamin A, 1,000s IU of vitamin E, and probiotics to aid in weight gain, body condition, and digestive function. Senior Flex is apple-flavored with a rice bran base for added palatability.

Also consider Senior Flex H/A Pellets!

View our Joint Supplement Comparison Chart


Active Ingredients per 1 oz:
(Maintenance Dose = 1 scoop (1 ounce) daily)
  • Yuca Schidigera Extract
    5,500 mg
  • Glucosamine Sulfate (Shellfish)
    5,000 mg
  • Methylsulfonylmethane (MSM)
    3,000 mg
  • Vitamin E
    1,000 IU
  • Ester-C
    1,200 mg
  • Chondroitin Sulfate (Porcine)
    500 mg
  • Direct Fed Microbials
    9.3 million CFU's
  • Vitamin A
    15,000 IU
  • Vitamin D
    5,000 IU
Inactive Ingredients:: Apple flavoring, dry sweetener, mineral oil, rice bran and yeast culture.


Instructions for Use:
Directions for Use: (1 oz measure enclosed) Adult Horses (900-1,100 lbs): Provide 1 ounce twice daily during high level stress and/or working conditions. For lower maintenance level, provide 1/2 measure twice daily. This level may be doubled for the first 14-21 days.

SmartPak has obtained permission from the manufacturer to administer the loading dose for 28 days for our customers who wish to add this supplement to their SmartPaks.

Clinical Research

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    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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    Senior Flex is rated 4.6 out of 5 by 135.
    Rated 5 out of 5 by from Supplement fantastic, packaging not so great I've had my horse on Senior Flex for over 10 years. It's the only thing that keeps his 36, almost 37 year old joints happy. However, the recent packaging change isn't the greatest. I saved my last bucket to pour it in, as the people who help care for my horse spilled the bag twice, as it's not nearly as stable as a bucket with lid.
    Date published: 2015-08-27
    Rated 5 out of 5 by from All around good product! I have used this product for many years on several horses. I now have 2 senior horses who both are in remarkable shape for their ages; the oldest is 29 now. I like that it has good, familiar ingredients I feel comfortable giving my horses, and can look at them and see how well it works! Plus, they love it!
    Date published: 2015-08-04
    Rated 5 out of 5 by from Great product Have been using Senior Flex for over a month now and my horse looks and feels great.
    Date published: 2015-02-13
    Rated 5 out of 5 by from Easy to use in smartpaks Giving this to our 28 plus year old appy and he is also a lesson horse and has more spunk than ever. Working great!
    Date published: 2015-02-03
    Rated 5 out of 5 by from Pleased with this supplement It took a little longer than a month, more like two months but now we can tell it is working. The automatic shipping to the barn makes it so easy!
    Date published: 2014-09-03
    Rated 5 out of 5 by from I'll never switch I have a 34 yr old QH gelding, who had a number of issues a few years ago, and without exploratory surgery, we would never know what was wrong with him, and on top of that he had severe damage to his front right knee due to getting smacked with a polo mallet. It resulted in debilitating arthritis to the point his nose would nearly touch the ground when he walked. After many trials and errors with both his digestive issues and the joint problems, I came upon Senior Flex. I was like a miracle. Within 2 weeks, his chronic diarrhea was clearing up, and his pronounced limp was disappearing. After being on Senior Flex for almost 9 years, I would never ever change. My mare is now approaching 30 and she'll be starting Senior Flex. And amazing supplement with amazing results!!
    Date published: 2013-09-19
    Rated 4 out of 5 by from Decent Supplement I've got an 18 year old with moderate arthritis. I was previously feeding just Yucca (at the same level) with great results, so I decided to try this product for some extra support. I didn't really notice any difference between this and just straight Yucca. When I run out, I'm going to try something with higher levels of ingredients plus HA. This product would probably be great for maintenance, but not so helpful when there's already damage done.
    Date published: 2012-10-18
    Rated 5 out of 5 by from
    Date published: 2012-10-08
    Rated 4 out of 5 by from Great for the price Compared to the active ingredients of the other Senior horse supplements, this has the edge and is extremely cost effective. My horse eats it no problem and has been acting a little more spunky lately! 4 stars becuase I only give my horse a smaller maintenence dose.
    Date published: 2012-08-29
    Rated 5 out of 5 by from Still works great I have used this supplement for over 6 years on the same horse. I have run out in the past and with in 1 week he is dead lame. He is a 28 y/o Morgan with degenerative suspensory disease in both back legs (I've owned him since he was 4 y/o). I was told he might be pasture sound at a walk - after having a long recovery he can buck, gallop and play like he use to (he is also sound to ride on safe ground at a walk/some trot.) Thanks to Senior Flex & Devil's Claw Plus I have my friend back.
    Date published: 2012-08-22
    Rated 5 out of 5 by from Great joint supplement! My 17 year old mare moves better with less crepitus after a month of use!
    Date published: 2012-08-11
    Rated 5 out of 5 by from Good general supplement for older horse!
    Date published: 2012-06-20
    Rated 4 out of 5 by from Excellent supplement My 23 yr old mare is doing great on this supplement. She a bit fussy about eating but she finds this supplement very palatable.
    Date published: 2012-06-04
    Rated 5 out of 5 by from Horse feel good! My 22 year old appendix seems to feel very good on this product! I caught him ripping around the field full speed leaving his younger pasture mate in the dust! I haven't seen him doing this in a while.
    Date published: 2012-04-24
    Rated 5 out of 5 by from Seems to work! Just barely a month in but I have noticed on my 12 year old show gelding that he no longer clicks when being ridden and the hock swelling he had been experiencing is gone. He seems to eat it with no problems. This is a good choice when your horse isn't ready for a Senior supplement with all the extras such Devils Claw and Boswellia
    Date published: 2012-03-13
    Rated 1 out of 5 by from This was great for my 24yr old thoroughbred's joints but not great for his breathing. He is a roarer and Seniorflex made his roaring so bad that I was unable to ride some days. If your horse has no breathing ailments then it is probably good.
    Date published: 2012-01-24
    Rated 4 out of 5 by from Great Value, Great Product My mare is definitely more spunky after being put on Senior Flex. She is back to her normal self again.
    Date published: 2012-01-23
    Rated 5 out of 5 by from
    Date published: 2011-11-13
    Rated 4 out of 5 by from
    Date published: 2011-11-07
    Rated 5 out of 5 by from Great Product! All my senior horses love this supplement. 3 of our horses have arthritus and can't tell due to the yucca in this product. I would definitely even recommend this product for horses that are borderline arthritus and joint inflammation. It is a great preventative AND Maintence of joint issues.
    Date published: 2011-10-03
    Rated 5 out of 5 by from Great product! We started using Senior Flex on my husband's 18 y/o QH gelding because he was having issues with mild lameness and swelling in his front knee due to arthritis. Within a month of starting the Senior FLex, the swelling went away and he was sound again. It has made him feel so much better. He runs around his pasture bucking just because he feels good. He doesn't mind the taste. We just mix it in his food and he eats every bit of it. I think it's definitely worth the money for the great results we've gotten. I don't plan on ever taking him off of it.
    Date published: 2011-09-28
    Rated 5 out of 5 by from Love it I have several over 25 horses and they look and act like teenagers. The vet was out to look at one of my mares and said she was about 15 years old. When I corrected him he was very impressed how well she looks. My horses love it and the results are great.
    Date published: 2011-09-22
    Rated 5 out of 5 by from
    Date published: 2011-08-19
    Rated 5 out of 5 by from LOVE IT!! I have two seniors, 21-year-old Thoroughbred mare and a 24-year-old Paso Fino gelding. This product makes a HUGE difference in how they move. I've tried other products, but they never work as well as this one! Best part is, if I forget to add Senior Flex to their grain, I can just dump it in their feed buckets and they'll clean it up!
    Date published: 2011-08-17
    Rated 5 out of 5 by from
    Date published: 2011-08-06
    Rated 5 out of 5 by from Very Good Product I have been using Senior Flex for a while with my 18yr. Old Quarter horse and he has shown inprovement. I would reccomend this to all my friends.
    Date published: 2011-07-07
    Rated 5 out of 5 by from The best product I've purchased in a long time! My very picky 25 yr old QH mare is a retired Western Pleasure/halter horse. At 15.3H and 1,350 lbs (in her prime), the weight took a toll on her joints. About 4 months ago she was so bad, she would lay down to take the weight off her feet and not be able to get back up without assistance. A vet visit later I was on this site finding the minimum recommendations provided by my vet. Today (late June) she walks around, trots, lopes, and gets up and down by herself just fine. She still has a little stiffness, but considering the drastic change in 4 short months I couldn't be happier, and it's Lacey approved! I also want to add that keeping weight on an older horse can be a feat. This is the only suppliment I currently have her on, and it's helped her digestive system use her in-take better. She's gained 50 lbs! This product is 5 stars and does wonders for the price.
    Date published: 2011-06-24
    Rated 5 out of 5 by from Love this supplement I have been using this supplement for a month and I could tell a difference in the short time I have been using it. My horse doesnt even knows its in his feed.
    Date published: 2011-05-31
    Rated 4 out of 5 by from
    Date published: 2011-05-25
    Rated 5 out of 5 by from Problem Solvers Senior Flex w/hyluronic acid has given my 26 yr old Q.H. mare who was very stiff in her joints more flexibility and given her a new lease on life.Quitt - It works!!!Farriers Formula - It has strengthened and improved my geldings hooves tremendously.
    Date published: 2011-05-18
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