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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
  • Ester-C®
    1,200 mg
  • Chondroitin Sulfate (Bovine)
    500 mg
  • Vitamin A
    15,000 IU
  • Vitamin D3
    5,000 IU
  • dl-Alpha Tocopheryl (Vitamin E)
    1,000 IU
  • Probiotic Blend (B. subtilis, B. licheniformis)
    250 million CFUs
Inactive Ingredients:: Active dry yeast (saccharomyces cerevisiae), heat stabilized rice bran, natural and artificial flavors and soybean oil.


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 137.
    Rated 5 out of 5 by from Wonderful Relief for Tinker Tried a free months supply of Senior Flex for my 27yr old mare. She was badly stocked up due to cold weather and arthritis. After starting her on this with a maintenance dose of bute she is noticeable comfortable and much more active. Very pleased with the results.
    Date published: 2011-03-10
    Date published: 2011-02-21
    Rated 3 out of 5 by from Economical Alternative I feed this to a 21 y/o mare and an 8 y/o mare. They were not fans of the texture as they were used to SmartFlex Sr. pellets. I think this is a good product for the price. My first pick will always be SmartFlex Sr but this provided an economical alternative.
    Date published: 2011-02-15
    Rated 4 out of 5 by from to use as a preventive My 12 yr. old has only been on it for 3 weeks. Bought to use as a preventive, to help ensure a long and lameless life. As far as palatability, she is a finicky eater, but she seems to enjoy senior flex
    Date published: 2010-12-25
    Rated 4 out of 5 by from Good solid value I am slowly working my way through all available joint supplements to make sure I've tried everything I can to help my arthritic 35 year old gelding be as comfortable as possible before I have to make the decision to put him down. Despite being a supplement skeptic, about 7 years ago I started him on Senior Flex and to my GREAT surprise, noticed a distict improvement in his mobility and comfort level. About 4 years ago I switched to the Smart Senior because I wanted a product with digestive and immune system support and I have since worked my way through several other products as his arthritis has advanced. Despite that his arthritis is now beyond what Senior Flex can help, he did show significant improvement on Senior Flex when his arthritis was less advanced. I do believe the Senior Flex is a solid product which provides a good value when compared with other similar products.
    Date published: 2010-12-23
    Rated 4 out of 5 by from Easy to Feed My two senior citizens are on this supplement and while I have no scientific evaluations to offer, they are thriving.
    Date published: 2010-12-20
    Rated 4 out of 5 by from So far so good... So far so good. We will see if it's any better than pure msm in a few months.
    Date published: 2010-11-12
    Rated 5 out of 5 by from good product I find that Senior Flex has a good combination of supplements to help support horses as they age. My aged gelding seems to be more comfortable since taking Senior Flex. He likes the taste which I have found to be a problem with other supplements of this type. I find this to be a good product that works for my horse.
    Date published: 2010-09-06
    Rated 5 out of 5 by from Awesome stuff I have a 18 year old mare that is able to still compete and win. It wouldn't be possible for her to even come out of her stall if it wasn't for the Senior Flex supplement. Really helps her joints and her all around body look great. Awesome stuff!
    Date published: 2010-08-11
    Rated 5 out of 5 by from Day & night difference I started my 16 year old QH mare Amber on Senior Flex last month because her gaits just didn't feel the same this year. She wasn't walking stiff, but she didn't didn't have her normal smoothness either so I figured at her age it couldn't hurt to try a joint supplement. Wow, I can't believe the amazing difference after only 3 1/2 weeks! She is smoother than she has ever been and is using her hocks and collecting more instead of pulling herself along on her forehand as she was starting to do at the trot and canter this year. I will keep her on this for the rest of her life and hopefully get many more years on the trail too with this added to her diet. Thanks Smart Pak!
    Date published: 2010-07-16
    Date published: 2010-06-24
    Rated 2 out of 5 by from Did not work for our gelding We tried this supplement for 8 weeks and saw no change. SmartPak rep helped us choose a new one to try. Just did not work for our guy
    Date published: 2010-06-24
    Rated 5 out of 5 by from A++ "I picked this product for my 22-year-old Paso Fino gelding after reading the ingredients and scanning the reviews. I wanted a product that entailed all the major senior needs without having to add another supplement and this product fit the bill. What really sold me was the added rice bran. My boy has been on the product for over a year now and I can really see a difference. He has more energy and his flexibility has returned. I don't remember his circles ever being this round before! I had to give this product five stars for palatability. One day he was grained without this supplement being mixed in, I panicked but threw a scoop full into his empty feed bucket. Wouldn't you know it, he stopped eating his hay and walked right up to clean his bucket for the second time. I was sold and this product has now landed on my must-have's for the barn."
    Date published: 2010-05-27
    Rated 5 out of 5 by from Worked Wonders for my Mare I bought this product for my 23+ year old mare who has a bit of arthritis in her hips. After about a month of being on this product, I saw changes in her. She even did much better for our farrier (who had problems doing her back feet before). She seems to be much more comfortable and much less stiff. I would absolutely recommend giving this product a try for anyone who has an older horse.
    Date published: 2010-05-17
    Rated 4 out of 5 by from great product!! My 24 yr old gelding injured his stifle area and was so sore and stiff,,, about 2 days after starting him on this product, he is moving freely and is trotting around with his buddies.... so I can tell it really is helping the pain and soreness!!! good stuff!
    Date published: 2010-04-14
    Rated 5 out of 5 by from WELL WORTH IT!!! I can't say enough good things about Senior Flex. It made our 20+ gelding look awesome and feeling great. No one recognized our old boy at the fair. It helped him put on weight, get a shiney coat and perform pain free. He and my daughter even brought home 2 grands. Thanks Senior Flex!
    Date published: 2010-04-08
    Rated 4 out of 5 by from Excellent product We bought this product for an older horse with arthritis problems. He is a very picky eater and wouldn't really eat other supplements. He eats this one and is doing really well so far.
    Date published: 2010-04-07
    Rated 4 out of 5 by from Senior Flex - more bang for the buck! This product is more cost effective and the horses LOVE it! Upon reading the labels, it has more glucosamine and MSM than other products that cost more - I tried it since it was cheaper! We have a few "senior citizen" horses that work hard - my son's 25+ roping mare and daughter's 19+ gelding running barrels and poles - they both move well and are pain free.
    Date published: 2010-02-08
    Rated 5 out of 5 by from Helps my Old Girl I just started using this product with my 24+ year old mare. She is usually very stiff especially when getting her hooves trimmed. I just had a visit from the farrier and she stood nice and quiet for him. It's amazing.
    Date published: 2010-01-18
    Rated 5 out of 5 by from Best Purchase Ever My horse feels great and works without any pain. The klicking noise you could hear from "shoulder in" is almost gone. He is not "old " yet, but I feel I support his health. This product is worse the money.If you want to do somthing good use it as preventive action.
    Date published: 2009-12-22
    Rated 4 out of 5 by from Great product for the money My older Azteca tends to be very picky but he loves this product. It really seems to help with his old joints etc.
    Date published: 2009-12-16
    Rated 5 out of 5 by from Great product! Glad that I took the advice of a very knowledgeable friend and ordered this product! In the short time I've used it, I've noticed a big difference. The ease of use is an added benefit also!
    Date published: 2009-12-08
    Rated 3 out of 5 by from so far so good i have my 21 year old half arabian mare on this product. i just started it, but it is edible and palable. with all the good stuff in it, i will know more in another month!!
    Date published: 2009-12-06
    Rated 4 out of 5 by from Good product I purchased this for my horse and my dog. My dog has arthritis and she is doing great. She seems to love the taste as well. My horse is finishing up her old stuff and can't wait to see how this will work with her. I am sure it will be great!
    Date published: 2009-12-04
    Rated 4 out of 5 by from Tasty & Seems to Help My picky eater readidy consumes this supplement as a top dressing of her food. Now that I have had her on higher amounts of joint supplement, she seems to be doing better wtih her gaits.
    Date published: 2009-11-02
    Rated 4 out of 5 by from Eaten by a picky mare I am always a little nervous when it comes to giving my mare a powdered supplement. I have given her liquid joint supplements in the past, but with winter coming that doesn't always work the best. Most powdered supplements end up in the bottom of her bucket, but I am happy to say that this one is always gobbled right up. Thank you Smartpak!
    Date published: 2009-11-02
    Rated 5 out of 5 by from Great for my horse Senior flex has made a huge improvement in my 20-something Paint. When we rescued him, he was in bad shape and did not want to move. We started him on Senior flex and he loves it! He is not sore anymore and loves to be ridden.
    Date published: 2009-10-19
    Rated 5 out of 5 by from Best Buy That Works I have used Senior Flex on 3 different horses with great success. I would caution users: A full scoop, after loading, can be too much and result in a VERY spunking horse! Senior Flex can make an old horse feel very good!!! For ongoing useage, I only have needed to use a half a scoop, depending on the horse and how you use him/her. You need to use your judgement. This is the best buy for the money.
    Date published: 2009-10-05
    Rated 5 out of 5 by from senior Flex my horse is an extremely picky eater. but he loves the flavor of senior flex
    Date published: 2009-10-02
    Rated 5 out of 5 by from Tried others, like this the best I have three retired horses ages 24 to 27 and this product has helped them to stay comfortable and enjoy life. Noone can believe that they are as old as they are. They all have arthritits but still can act like yearlings, thanks to this product.
    Date published: 2009-09-02
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