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SmartFlex® Senior Powder Original

SmartSupplements by SmartPak — Item #14665
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Best-selling senior formula

  • 7,000 mg of glucosamine, 500 mg of chondroitin sulfate & 50 mg of HA for healthy joints
  • 1,750 mg of devil's claw, 500 mg of boswellia & 300 mg of phenylalanine help manage discomfort
SmartFlex Senior was designed to support older horses in the three areas they need it most – joint health, digestive function, and antioxidants for a healthy immune system.

For joint support, SmartFlex Senior provides 7,000 mg of glucosamine, 500 mg of chondroitin sulfate, 50 mg hyaluronic acid, and 12,000 mg of MSM. This formula contains the herbs devil’s claw and boswellia, as well as the amino acid phenylalanine, to help manage discomfort. To support healthy digestion, SmartFlex Senior provides probiotics, prebiotics, and enzymes. And because senior horses benefit from extra antioxidants, this formula also contains vitamin C and super oxide dismutase. This outstanding formula is a customer favorite!

For even more comprehensive senior support, consider our multi-purpose formula SmartCombo Senior.

View our Joint Supplement Comparison Chart

Find your horse's SmartFlex


Active Ingredients per 30 g:
(Maintenance Dose = 1 scoop (30 g) daily)
  • Methylsulfonylmethane (MSM)
    12,000 mg
  • Glucosamine HCl (shellfish)
    7,000 mg
  • Devil's Claw Extract
    1,750 mg
  • Chondroitin Sulfate (bovine)
    500 mg
  • Boswellia Extract
    500 mg
  • DL-Phenylalanine
    300 mg
  • Calcium Ascorbate (Vitamin C)
    275 mg
  • Fructooligosaccharides
    225 mg
  • Super Oxide Dismutase (bovine)
    100 mg
  • Sodium Hyaluronate
    50 mg
  • Pancreatin 8x (supplying Amylase, Protease, Lipase)
    30 mg
  • Profloratin® (a proprietary blend of L. acidophilus, L. casei, E. faecium and B. longum)
    4.7 billion CFU
Inactive Ingredients: : Cherry Flavoring, Magnesium Silicate.


Instructions for Use:
Horse Weight Recommended Amount
Under 500 lbs. 0.5 scoops
500 – 1000 lbs. 1 scoop
1000 – 1500 lbs. 1 scoop
Over 1500 lbs. 1.5 scoops
Directions for Use: Administer 30 g daily, 1 scoop = 30 g.

Clinical Research

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    SmartFlex® Senior Powder Original is rated 4.6 out of 5 by 653.
    Rated 5 out of 5 by from Mare prefers My mare has been on the pelleted formula for several years, but over the last two years, has started to refuse to eat her supplements and then refused to eat her grain. Switched to this powder version and now she eats it right up.
    Date published: 2016-10-27
    Rated 5 out of 5 by from Huge Improvement I bought this for my 33 yr old QH mare, Sunny and 30 yr old TB gelding, Peate. Both showed huge improvements in about a month on this supplement. They have been on it since Dec 2015. Sunny use to be on the Seniorflex brand over ten years ago and did well but would not eat it. She is probably the pickiest horse I know. She will eat Smartflex with no issues! She is a pasture puff now and before Smartflex would slowly walk into the barn, now most days she has a pep in her step and will even trot or do a brief canter! Peate is still able to be ridden and is used in a small lesson program. Smartflex has made a huge difference in him and seems more comfortable under saddle! Highly recommend this product!
    Date published: 2016-10-13
    Rated 5 out of 5 by from Month 2! After the first 30 days I saw such a huge improvement in my horse I had to keep her on this product to see if she will continue to improve. My horse was so lame she couldn't trot without being in pain. After just 30 days she's beginning to canter in the field. I am hoping I can start riding her again.
    Date published: 2016-07-28
    Rated 4 out of 5 by from Misty is holding her own. Misty doesn't seem to do as good on this as the other , maybe it just takes longer.
    Date published: 2016-07-15
    Rated 5 out of 5 by from SmartFlex Senior Powder I bought this product for my 27 years old Quarter horse gelding. He seems to be doing well on it. I have 3 horses on Smart Pak products and i am very impressed with the results on all 3 horses.
    Date published: 2016-07-06
    Rated 5 out of 5 by from Works great I have used this supplement before on my older gelding before he passed away. It worked great and my 28 year old former Hunter was still sound and happy.
    Date published: 2016-04-04
    Rated 4 out of 5 by from Good product My horses have been on this for so long, I am afraid to find out what they would be like without it. They are 27 and 30 and still running around, so it must be helpful. They both have arthritis, that I know, but the 30 YO is always trotting around, so it has to be helping. Palatability - not sure - smells sweet. The 30 YO eats everything, the 27 YO is pickier, but since they get lots of supplements, not sure which one may be causing pickiness. She eats everything, reluctantly.
    Date published: 2016-02-29
    Rated 5 out of 5 by from Shiny and happy Token is a 23 yr old OTTB who has been on this product six weeks. His coat is way shinier, he's not creaking when he walks in the hind end, he definitely seems more comfortable and very pleased with himself. He's had no problems eating it either. I love it
    Date published: 2016-01-20
    Rated 5 out of 5 by from My Senior is eating well I just started my 22-year-old Cushing's horse on the supplement. He is eating well but it's too early to tell any difference.
    Date published: 2016-01-08
    Rated 5 out of 5 by from Defiantely a difference I have seen a major difference in my mare with this. She has next to no swelling and has been completely sound after a NASTY joint infection that cause DJD I was very worried she would not be sound again. But she is doing great!
    Date published: 2015-09-02
    Rated 5 out of 5 by from Taking care of the ones who have taken care of us! I started my older mare in this a few months back and she has been doing great, 19 this year and still competing!
    Date published: 2015-07-20
    Rated 4 out of 5 by from Seems to make a difference! Gave this to my husbands old roping horse who is getting a new job in life as a trail horse. I have definitely noticed improved movement. He isn't as stiff and seems to be more eager to work.
    Date published: 2015-07-16
    Rated 5 out of 5 by from Great for Arthritis My mare has a small amount of arthritis in one fetlock. This made her sound in two days. Gotta Love it.
    Date published: 2015-06-01
    Rated 5 out of 5 by from Solved Supplement Problem guy My Quarter Horse stallion is 27 years and an ornery old guy. He was not named The Black Rattler for nothing. He has had continuous problems with loose stools which still had our vet puzzled after many tests. Daily washing and salving his hind area was not improving his disposition either. Finally by process of elimination we traced it to pelleted supplements. We depend on SmartCombo Senior to keep all our old guys fit but this supplement does not come in powder form. Fortunately SmartFlex Senior does. Switching "Black" to SmartFlex Senior powder worked. His stools are now normal and his joints get all the support they need. The Black Rattler will always want to let you know he's boss, but he is much more civil about it
    Date published: 2015-05-15
    Rated 5 out of 5 by from Great Product That Really Works I have two 22 year old horses (thoroughbred and part Arab) on SuperFlex Senior. Within a month we all saw change (for the better) in both horses. While both horses had been on another joint supplement for over a year, we saw better improvement with SuperFlex. Strides were longer and smoother, not as stiff under saddle, and even in the field the two were trotting and cantering more often. There was no problem with them eating it, and the part Arab is a very picky eater.
    Date published: 2015-04-08
    Rated 3 out of 5 by from First time use My gelding is older so I hope this works. It's my first time ordering this so fingers crossed. For his first month I didn't expect to see anything major but hopefully now on our second month we will see improvement.
    Date published: 2015-03-27
    Rated 5 out of 5 by from Moving well 25 yr old mare is once again leaping in the air on the lounge line! Wasn't sure I would see that again. Very satisfied with results.
    Date published: 2015-02-24
    Rated 4 out of 5 by from Helped get rid of the stiffness! I bought this because I have a 19 year old appendix in moderate work. I wanted a joint supplement that would go up and above just the regular joint supplement you find on the shelf. Smart Paks smartflex senior has truly helped my mare! She is completely more brave in her work! She is no longer stiff and I don't have to spend as much time warming up. I love this product!
    Date published: 2015-02-17
    Rated 2 out of 5 by from Pony Didn't like taste Got this product and my Pony didn't like the taste of it, and would move it to the bottom of her bucket
    Date published: 2015-02-02
    Rated 5 out of 5 by from Appealing formulation I have one elderly gelding and one permanently lamed middle-aged mare who have been using a powder formulation of a senior joint supplement for maintenance and general health. There was a great deal of waste in the powdered formulation left in their buckets every day. They are very enthusiastic about eating the pelleted formulation
    Date published: 2015-01-09
    Rated 4 out of 5 by from Good choice for seniors My 23 yr. old retired TB is noticeably more comfortable since starting SmartFlex senior
    Date published: 2015-01-07
    Rated 5 out of 5 by from I believe in Miracles I bought some smartflex senior joint supplement for my 25 year old thoroughbred gelding. He's got some really gnarly arthritis from his racing days and had recently been having some trouble getting up after laying down to the point where a vet had to be called out. He was down for at total of 13 hours both times and we thought we were going to lose him. After a month of being on smartflex senior, he's a different horse. His eyes are bright, he's trotting and loping around my younger horses like he owns the place, and he's able to stand up after a nap with ease. I cannot thank smartflex senior enough for giving my old guy another chance.
    Date published: 2015-01-01
    Rated 5 out of 5 by from Works wondwrs I have my 24 year old on this. Started my 14 year old on it this month.
    Date published: 2014-12-30
    Rated 4 out of 5 by from Good product My 17th old gelding is eating it up. I like that it's a powder, and the daily dose is easily added to his small ration.
    Date published: 2014-12-15
    Rated 3 out of 5 by from too early to tell Have not seen much change yet I think it is still too early to twll
    Date published: 2014-12-05
    Rated 4 out of 5 by from Perfect for my Seniors I was on the hunt for an affordable supplement to help my seniors get around. Out of my three senior horses, only one is ridden on a regular basis..the others maybe once a week. I wanted something affordable but also with natural anti-inflammatories to help out with their stiffness. I found all of this and more in the SmartFlex Senior. Within a week I noticed a difference in all three of my seniors. Very Happy!
    Date published: 2014-11-24
    Rated 5 out of 5 by from Made a huge difference in my Senior. My senior has arthritis and this product, along with several others from SmartPak, have helped him so much. He used to limp and be quite stiff, but now he comes out of his stall ready to go!
    Date published: 2014-11-21
    Rated 5 out of 5 by from Amazing results for my mare I am completely in awe of the changes my 20yo mare has gone through the past few months she has been on this joint medicine. She was LAME from arthritis, ring bone and side bone, plus an accident, and she now trots across the arena to me. Amazing results and I put my other less senior boys on it as well as my performance horse on the II. Hoofs crossed for similar results!
    Date published: 2014-11-06
    Rated 5 out of 5 by from Love this product! My mares been on it for over 2 months and doing great!
    Date published: 2014-11-04
    Rated 4 out of 5 by from Good results so far! Seems to be helping 30++ year old mule. She seems less stiff.
    Date published: 2014-10-21
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