Many horse owners are interested in GutX as an alternative to GastroGard, which is the only FDA-approved treatment for Equine Gastric Ulcer Syndrome (EGUS). This article explores what we know about GutX as a horse ulcer supplement for both treatment and prevention.
We’ll cover GutX’s active ingredients, the limited studies that are available, anecdotal evidence (including mine), and similar supplements for horses with ulcers.
What is Gut X by 100X Equine?
GutX is a supplement that purports to offer a safe, relatively inexpensive, non-pharmaceutical alternative for the treatment and prevention of Equine Gastric Ulcer Syndrome (EGUS). It is one of several products offered by 100X Equine, a company known for its fun, if rather aggressive, marketing and always-on-sale prices.
The product label indicates that GutX offers “daily digestive support” to “target ulcerated tissue,” “support good gut health, and “boost immune response.” The product is said to contain a “proprietary blend of ingredients to soothe the stomach and combat hindgut acidosis.”
The company suggests feeding a loading dose of 2 oz per day for 30 days, followed by a maintenance does of 1 oz per day. They also add that the higher dose may be continued in for horses that have “severe gastric issues” or are in stressful circumstances, such as travel and competition.
The hope is that this inexpensive horse ulcer supplement can circumvent potential PH alterations and acid rebound from extended use of proton pump inhibitors — that is, the omeprazole in products including GastroGard and UlcerGard.
But does it work?
Active Ingredients in the Horse Ulcer Supplement Gut X
GutX is a gel comprised of hyaluronic acid (200 mg/oz) and beta glucan (100 mg/oz), plus a handful of inactive ingredients. Let’s take a look at the active ingredients.
Hyaluronic Acid, aka HA or Hyaluronan
Not being a chemist, molecular biologist, medical practitioner, or scientist of any kind, I went looking for a layman’s definition of hyaluronic acid. The Matrix Biology Institute, a non-profit dedicated to the study of HA (primarily in humans) puts it like this:
“Hyaluronan is a unique polysaccharide molecule filling the space between the cells of the human and other vertebrate bodies. It is unique in the sense that it is present in all connective tissues of the body and is a pure polysaccharide… [I]t forms a very viscoelastic fluid that fills the space between collagen and elastin fibers and the proteoglycans that fill the space between cells.”
Basically, all our bodies — and those of our horses — naturally contain a bunch of this gooey stuff that does things like make our skin plump and our cartilage slick. Additional HA can be added to the body thorough injections, intravenously, or orally.
Most of the information I found about HA in horses focuses on its benefits for connective tissue health. Indeed, HA makes regular appearances in equine joint supplements. However, the Slovis study described below includes a helpful description of the possible benefits of HA in the gut.
I asked 100X Equine about the proposed mechanism of action of HA in GutX. They responded that this ingredient “regulates PH, brings moisture to the area, and addresses pain and inflammation associated with ulcers and/or hindgut acidosis.”
Beta-Glucans
Beta glucans are soluble fibers that represent one of the dominant forms of polysaccharides in a variety of plants, bacteria, fungi, algae, and yeasts. They are used in both humans and horses to confer a variety of health benefits, from wound healing to immune modulation.
What about gut health and treatment of equine ulcers? The immune-boosting factor would seem to be relevant, since much immune activity takes place in the gastrointestinal tract. Indeed, myriad equine supplements featuring beta-glucans — usually extracted from oats, barley, mushrooms, or yeasts — claim to benefit gastrointestinal health. You’ll find them in many supplements for horses with ulcers. GutX, of course, is among them.
However, since beta-glucans are fermented in the horse’s hindgut, it is not clear that they are helpful for stomach ulcers in particular.
My Experience with Gut X
I wrote this post in January 2023, after having my horses on GutX for over a year, and have updated it every few months. My horses didn’t object to the product’s taste, and I appreciated that the gel helped other, powdered supplements stick to top-dressed pellets.
When I first ordered GutX, a company representative told me that many endurance riders dramatically increase dosage (to upwards of 6 oz daily) during travel and events. Personally, I fed the maintenance dose plus an extra ounce before workouts or trailer rides. At rides, I gave my horses two ounces per day if they were just in camp, plus another ounce at each hold if they were competing.
Initially, GutX did appear to help my very anxiety-prone mare whose symptoms repeatedly returned after treatment with omeprazole. Unfortunately, the moment I took her to ride camp, her symptoms returned with a vengeance. GutX was insufficient to get her past them, and I eventually sold her to a home where she could enjoy a more easygoing lifestyle.
A few months later, another horse started exhibiting ulcery behavior. I had him scoped, and we found minor tissue inflammation, particularly in his pylorus. It wasn’t even close to obvious, bleeding ulcers, we but decided to treat with a GastroGard and sucralfate protocol because his behavior was so dramatic. Ultimately, we ended up administering misoprostol to achieve full resolution.
Unfortunately, this is an example of how even scoping doesn’t necessarily give us clear, complete answers regarding the efficacy of GutX. Would my horse’s stomach have been in worse condition without the supplement?
Maybe! Or, maybe not.
Ultimately, as I dug more into the research, I moved on to other ulcer supplements. Let’s take a look at what the literature had to say.
Does Research Support Gut X for Treatment of Equine Ulcers?
Anecdotal reviews overwhelmingly report either improvements in the behaviors and appearance associated with EGUS or continued absence of symptoms in previously unaffected horses.
This is true both on 100X Equine’s own website (for which they aggressively solicit reviews) and in forums, blog posts, and social media sources over which the company has no control.
Maybe there’s something to it.
On the other hand, actual studies supporting the efficacy of GutX and its ingredients for gut health aren’t as robust as one might wish. Let’s take a look.
The Slovis Study
The best known study on the subject is the Slovis study published in the Journal of Equine Veterinary Science in 2016. Ten horses with squamous and glandular gastric ulcers were treated with oral HA and schizophyllan, which is a beta gluten polysaccharide. Gastroscopy was used to compare before-and-after images, and the horses’ trainers provided observational data. Nine out of the 10 horses showed significant healing after 30 days.
Unfortunately, the Slovis study had a weakness acknowledged by its author: all the equine participants were treated; there were no controls. In other words, we can’t be sure that the ulcers wouldn’t have healed on their own, which is possible. That seems somewhat unlikely to me, given that the horses were maintained in their usual environments and work. Presumably, they hadn’t healed under those circumstances for some time prior to the study.
The Svagerko Pilot
The plot thickens when we read this 2021 pilot study , which was published as a master’s thesis by Clemson University student Peyton Svagerko. Eight horses were scoped 3 times over 6 weeks, during which they were fed an unspecified polysaccharide supplement. At the end of the study, all 8 horses showed similar reduction in ulcer severity…including the 4 controls.
Like Slovis, Svagerko was looking only at the treatment of existing ulcers. In her conclusion, she notes that “The investigation of polysaccharide supplementation as a preventative measure in ulcerative and non-ulcerative horses under stress is warranted.”
I agree completely.
I asked 100X Equine whether they’ve had and opportunity to review and respond to the Svagerko pilot. A year and a couple followup messages later, I haven’t heard back, but I will update this post if I ever do.
The Unofficial Study
Deep in the Resolvet website, I found a report of what appears to be an unofficial, unpublished, blind study done by Allison Foil, DVM, for one of her clients. Apparently, they scoped 150 horses and observed significant, positive outcomes in individuals treated with Haygard’s Relyne GI, which is an HA and beta glucan gel similar to GutX.
Comparison of Gut X to Similar Products for Treatment of Equine Ulcers
Both GutX and Relyne GI use proprietary blends, so I’m not able to compare them perfectly. Relyne GI appears to contain 50% more HA per ounce than GutX. I wasn’t able to locate the quantity of beta glucan it contains.
Interestingly, respected veterinarian Shane Smith, DVM, observed during his keynote at the 2023 PNER Convention that he and his colleagues at Idaho Equine Hospital tried Relyne in the past without great success. Dr. Smith also noted that Idaho Equine scopes horses that have been on GutX and finds ulcers. I have no details regarding the frequency and dose of GutX those horses were receiving.
The amount of HA fed in the Slovis study was more than is in an ounce of GutX, but consistent with the amount in two ounces. The amount of beta glucan was similar to the amount in an ounce of GutX.
There are many alternative forms of HA and beta-glucan on the market. These include well-known products like Succeed (beta-glucan) and Ortho-Chon HA (hyaluronic acid and more, targeted for joint health). You can also find a smorgasbord of HA and beta-glucan powders and capsules in the online marketplace, if you’re willing to do your homework or take a risk on quality.
In response to my inquiry, 100X Equine stated that their HA blend contains a range of high molecular weights (1.0-3.0 Million Dalton), which they say is important to “maximize all aspects of the HA.” The gel is extracted through microbial bio-fermentation of Bacillus Subtilis.
The beta glucan in GutX, like Slovic’s, is schizohyllan. 100X Equine says the micronization of their beta-glucan is “critical for proper absorption.” They also claim that the whole ingredients used in some of their competitors’ products, particularly those in dry form, don’t have time to break down for absorption during digestion.
My Conclusions and Recommendations
In a perfect world, I’d be able to look at studies on GutX itself, not just its active ingredients. I’d also like stronger evidence that the HA-beta glucan combination of ingredients treats or prevents ulcers.
Alas, this isn’t a perfect world. While absence of scientific proof doesn’t necessarily mean a product isn’t effective, I’d rather err on the side of products whose ingredients are supported by a wider body of research.
When I strongly suspect ulcers, I’m inclined to go with my vet’s recommendation (typically to scope and/or treat with GastroGard) rather than throwing supplements at the problem. However, I have had success with natural ulcer treatment in a rescue horse.
For ulcer prevention, I use supplements…but GutX is no longer among them. Instead, I’ve added Mad Barn’s Visceral+ to my horses’ regimen. Why Visceral+? Its research-backed ingredients are provided at physiologically relevant levels to support the horse’s natural gastric healing mechanisms and immune response. You can read my deep dive into Visceral+ here.
In addition, I continue to maintain baseline EGUS prevention strategies: free access to forage (pasture is ideal, but I have to go with hay), minimal hard feeds, and feeding alfalfa or outlast before workouts or hauling.
Are you going to try GutX for treatment or prevention of equine ulcers?
If so, I recommend taking a scientific-ish approach. Most people who use GutX won’t be paying for before-and-after gastroscopy. If that’s you, it’s worth your time to take notes, photos, and video both before supplementing and at frequent intervals thereafter.
Observe your horse’s appearance, attitude, and behavior. Consider other factors (travel, new pasture mates, changed workload, etc.) that could influence outcomes. Be mindful of your normal, human tendency to believe something works because you really want it to. Keeping careful notes will enable you to more objectively assess the efficacy of the product in your horse’s case.
If you try this, circle back in the comments and tell me how it goes!
Trying Visceral+ instead?
Use my coupon code 5%OFF-FROM-TAMARA-B to get 5% off your first Mad Barn order — that’s up to $28 off Visceral+!
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Thank you for the post and the updates! I certainly go back and forth with my thoughts on Gut X. My horse ended up at the ICU at UC Davis last year – we never had a conclusion diagnosis but they believed he had an acute case of ulcers that was causing him to colic (he was scoped). Anyway, we treated him with GastroGard and sucralfate and after that, I started him on Gut X and SmartPak’s Smart Combo Ultimate Pellets. I was introduced to Gut X by a friend who was a vet tech for our barn’s vet (though the vet said she’s never heard of the product) and she said it was working for her horse. Since hyaluronic acid is also good for joints and Gut X is relatively affordable, I figured, why not! We’ve been using it for 1.5 years now and i can’t really confidently say it’s doing something (I mean, he’s fine but we also haven’t scoped him) but I can also say it hasn’t done him any noticeable harm. I’m a little scared to stop it because #anxiety and like you said, how do we know if he’s fine because it IS working vs he’s fine because he’s…fine. Do agree it would be great if 100X Equine could publish more science-backed research or even just metrics.
OMG, yes, I totally understand that experience! I do like to think the HA is helpful for joints, if nothing else, though it’s my understanding the effectiveness of oral HA generally — let along this product in particular — is also a subject of some debate.
Hi Grace ~ I totally agree! Would love to hear what happens if you ever do decide to take him off it. I have most of mine off GutX now ~ just using it up with a couple still ~ and haven’t noticed any difference. But, like you said…
This is so hard, trying to do the best for our horse(s).
I acquired & moved my guy (3/21) with a preventive 10-day course of Gastroguard. He was Dx EPM & colicked (6/22) and had “screaming” ulcers (2/23). A compounded Omeprazole and misoprazole did help significantly. I added Purina Smart Omega Match (@ 2lbs) which provides a dose of Outlast, as the best boarding I could find locally had pen life with 2hrs of pasture T/O, with grass hay. In the meantime, my vet recommended the Resolvet RelyneGI; I pre-filled syringes for the staff to add to his supplements. In May he was working well at the trot, but angry at feeding time. I had been using slow feeders for over a year to try and keep hay in front of him as much as possible!
Fast forward to a move to FT pasture (6/23), an hour away. I have no control over the quality of the pasture or hay, but his attitude is significantly better with the move. I’m finishing my 2nd 64 oz bottle of Relyne, and am hesitant to reorder…is it really helping? The biggest problem he has—besides loss of topline—is a bloated, gassy “hay belly,” after moving his herd of 6 to a different pasture for Fall. Plus, the pastures are bleak now. I’m going to try Formula 707 Digestive Health. I’ve tapered Omega Match, and added back Triple Crown Sr for some beet pulp, fat & fiber for the winter. I’m tempted to switch to Triple Crown Balancer!
Something needs to change, he’s not quite right.
Keep the comments coming about the GI options, HA options & anecdotal results!
Loss of topline + “grass belly” = test for Cushings if you haven’t already + if he’s at a reasonable age for it (i.e. if he’s 3… yeah probs not cushings haha!) You probably already thought of this but chiming in just in case.
You should do a similar review of the Visceral+!
Ooo, let me think on that! I am still very happy with Visceral+!
This post is super timely, My vet recommended GutX but my read of people’s experiences has not lead me to believe it will be effective. I was considering Ukeles’ G.U.T. product because it has the beta glucan, which supposedly helps.. I don’t know, its all so frustrating…
Hi Jen — That’s super interesting that your vet recommended GutX! I wonder if s/he has managed to get ahold of some research that I didn’t find, though I felt like I turned the internet upside-down. LOL I’ve settled on Viscaral+ because I feel like its ingredients have the most research behind them, individually. I tried G.U.T. many years ago without luck, but that was a very challenging case and I’m not sure it was the product’s fault!
I’ve been going down the rabbit hole for ulcer prevention/maintenance now that we’ve stopped omeprazole after 3 months. Do you (or anyone else) have any opinions on Equine 74 Gastric and Finish Line U-7 Gastric? Visceral+ is on my list, but I haven’t placed my order yet. I’m one of those people that has to do a million hours of research before pulling the trigger.
It is such a rabbit hole! I haven’t tried Equine 74 Gastric or the Finish Line product. Hopefully, someone else will chime in! If you try them, I’d love to hear how it goes.
I don’t like the advertising of gut x. They seem like a scam when they say $back gaurentee. That alone is a joke.
I did purchase 2 gallons at a sale,which only one is able to return,but nobody will because of rules.
Didn’t help after 2 months,one mare did seem more happy with new mare. Did not help liquid squirt out of butt at all,or undigested hay.
With that being said,I used equine probios and within 2 days totally took care of squirts, helped with poop texture but still battling that. Probios is cheap, they have treats that make it easy and they love them
I also do use outlast ,same problem….Does it work or would they be the same without?
I hear you! This is the great frustration of supplements, no? Sigh.
My experience with GutX – a bit worrisome perhaps?!
I bought GutX after seeing ads on Facebook and reading testimonials on posts as well as their page. My horse, Butterscotch, was cinchy even out in the pasture if you just touched that area with no saddle around so I worried about ulcers although she didn’t have any other symptoms really and not really many of the risk factors. I called 100Equine (GutX) to discuss her symptoms, and they were very friendly and said they thought it would be great for her, and to give more, not less to her, b/c if it isn’t used by the body, they would just expel it. I started her and my very first horse who was 19 years old on GutX. Here’s where it gets disconcerting. After about 5 days, my sweet first horse colicked and had to be put down (an awful day). I chalked up the GutX to coincidence although I did message them to let them know in case they started hearing more stories such as this and it was not coincidence. They messaged back condolences, but didn’t say anything about their product which was probably a professional way to handle versus becoming defensive, and again, I even told them I thought it was likely a coincidence. I kept Butterscotch on it with 2 squirts daily, but didn’t really feel like there were any changes. Therefore I called 100Equine to get their thoughts and they said to up the dose to 3 squirts a day which I did starting about 8-9 days ago. Well, I noticed this Monday she seemed a bit “off” but she was eating and walking around fine, and so I let it go. Then the next day, she was laying down, but got back up. She was extremely guarded of any touching of her belly especially cinch area, and wouldn’t eat. Gave her banamine, called my vet and discussed what was going on, and thought she was getting better, but then Wednesday (today) she was still off, still not eating, and so I called my vet who was backed up b/c it was a half-day because it’s the day before Thanksgiving. I ended up taking Butter to Virginia Tech Veterinarian Hospital where they did an ultrasound and labs thus far. The findings thus far are a slightly “rounded liver” and elevated triglycerides. They are not sure what’s going on. I told the vet about GutX as I was freaking that not only did I possibly hurt this horse, but killed my other mare. The vet said that she thought it was unlikely that GutX would have caused these issues- perhaps to alleviate my worry. My teen son who helps with the horses, immediately yesterday said, “Mom, I think it’s that GutX! Magic started with it and colicked, and now Butterscotch is now sick after we started giving her a higher dose.”
Again, the vet thought it was coincidence, but did tell me to not give any more of it. Also, in her opinion, and her focused career she explained is in research of Equine Gastric Health, is that GutX doesn’t work. I just wanted to let others know about what has happened with my horses b/c if anyone else has a story like mine, perhaps it’s more than a coincidence. I’ve read that some people think GutX has made a positive difference for their horses, and I think that’s great, and I truly hope there’s nothing to ever be worried about if using it, and that my experience is inconsequential.
Thank you for sharing your story! I hope Butter is okay!!