Stop Guessing — Eliminate the Parasites Already Inside Your Horse
Most horses carry internal parasites right now, and the damage happens long before you see symptoms. One trusted dose can clear the spectrum that cheaper dewormers miss.
The Problem
Your Horse Looks Healthy — But Parasites Are Already Costing You
It starts with something small that you almost explain away. Your mare's coat looks a little dull going into fall, but you chalk it up to the season changing. Your gelding comes in from the paddock eating normally but drops a few pounds over six weeks — you adjust his feed, add a supplement, wait. Nothing quite adds up, and no single sign is dramatic enough to demand immediate attention. That's exactly how internal parasites work: slowly, quietly, and invisibly until the damage is done.
The barn life makes it easy to miss. You're managing four horses, a job, and two kids in school. You deworm on a rotation the way your trainer showed you years ago, and most of the time everything seems fine. But "seems fine" and "is fine" are very different things when you're talking about bots burrowing into the stomach lining, arterial stages of bloodworms disrupting blood flow, or ascarid burdens silently taxing a young horse's developing system.
Veterinarians will tell you that strongyle larvae — particularly the arterial stages of Strongylus vulgaris — can migrate through blood vessels and cause colic episodes that look like they came from nowhere. These aren't edge-case scenarios. They're well-documented consequences of incomplete parasite management, and they happen on well-kept farms with attentive owners every single year. The problem isn't neglect; it's that not every dewormer reaches every parasite.
The hardest part is the uncertainty. You're doing the responsible thing — you're deworming regularly — but you can't see what's happening inside your horse. You rely on the product to do its job completely, and if it doesn't cover the full parasite spectrum, you won't know until you're calling your vet at midnight wondering why your horse is colicking in December.
The barn life makes it easy to miss. You're managing four horses, a job, and two kids in school. You deworm on a rotation the way your trainer showed you years ago, and most of the time everything seems fine. But "seems fine" and "is fine" are very different things when you're talking about bots burrowing into the stomach lining, arterial stages of bloodworms disrupting blood flow, or ascarid burdens silently taxing a young horse's developing system.
Veterinarians will tell you that strongyle larvae — particularly the arterial stages of Strongylus vulgaris — can migrate through blood vessels and cause colic episodes that look like they came from nowhere. These aren't edge-case scenarios. They're well-documented consequences of incomplete parasite management, and they happen on well-kept farms with attentive owners every single year. The problem isn't neglect; it's that not every dewormer reaches every parasite.
The hardest part is the uncertainty. You're doing the responsible thing — you're deworming regularly — but you can't see what's happening inside your horse. You rely on the product to do its job completely, and if it doesn't cover the full parasite spectrum, you won't know until you're calling your vet at midnight wondering why your horse is colicking in December.
Why It Keeps Happening
Why Rotating Dewormers Doesn't Always Protect Against the Worst Ones
The conventional wisdom about deworming has been 'rotate your products' — switch between drug classes so parasites don't build resistance, cover different species throughout the year, stay on a calendar schedule. That advice has value, but it also creates a false sense of security if the products you're rotating don't address the parasites that cause the most serious harm. You can rotate three mediocre products and still leave your horse vulnerable.
The benzimidazole class of dewormers — products like fenbendazole and oxibendazole — has faced growing resistance problems in strongyle populations worldwide. Decades of heavy rotation have allowed resistant populations to flourish, and many farms are unknowingly treating with products that small strongyles have already learned to survive. Your horse is dosed, your calendar gets a checkmark, and the parasites carry on. The label says 'effective' — but effective against what, and against resistant populations specifically?
Bots are another case where riders often assume they're covered when they're not. Many common dewormer classes don't kill bot larvae effectively. These larvae — deposited as eggs on your horse's legs and shoulders during fly season — are ingested when your horse grooms, attach to the stomach lining, and spend the winter there. If your deworming program doesn't specifically address bots with a product that can kill them, you may be completing your fall routine with bot larvae still embedded and actively damaging gastric tissue.
There's also the issue of timing and coverage gaps. Some products work only on adult parasites; others hit larval stages. Some miss arterial migrations entirely. Riders who faithfully deworm three times a year may still have a window — sometimes months long — where migrating larvae are active and untreated. The biology doesn't pause for a convenient deworming schedule, and a product that can't follow the parasite through its life cycle can't stop the damage it does along the way.
The benzimidazole class of dewormers — products like fenbendazole and oxibendazole — has faced growing resistance problems in strongyle populations worldwide. Decades of heavy rotation have allowed resistant populations to flourish, and many farms are unknowingly treating with products that small strongyles have already learned to survive. Your horse is dosed, your calendar gets a checkmark, and the parasites carry on. The label says 'effective' — but effective against what, and against resistant populations specifically?
Bots are another case where riders often assume they're covered when they're not. Many common dewormer classes don't kill bot larvae effectively. These larvae — deposited as eggs on your horse's legs and shoulders during fly season — are ingested when your horse grooms, attach to the stomach lining, and spend the winter there. If your deworming program doesn't specifically address bots with a product that can kill them, you may be completing your fall routine with bot larvae still embedded and actively damaging gastric tissue.
There's also the issue of timing and coverage gaps. Some products work only on adult parasites; others hit larval stages. Some miss arterial migrations entirely. Riders who faithfully deworm three times a year may still have a window — sometimes months long — where migrating larvae are active and untreated. The biology doesn't pause for a convenient deworming schedule, and a product that can't follow the parasite through its life cycle can't stop the damage it does along the way.
The Solution
One Syringe That Follows the Parasite All the Way Through
Zimecterin is an oral equine deworming paste built around 1.87% ivermectin. Rather than using a benzimidazole or organophosphate, the label identifies ivermectin as the active ingredient and lists treatment and control of large and small strongyles, pinworms, ascarids, hairworms, large-mouth stomach worms, lungworms, intestinal threadworms, bots, and specified causes of summer sores and dermatitis. The label also includes fourth-stage small strongyle larvae, early Strongylus vulgaris forms in blood vessels, and oral and gastric bot stages. That stage-specific labeling is the practical reason to choose Zimecterin for a veterinarian-directed ivermectin treatment.
Each 0.21 oz (6.08 g) syringe contains enough paste for one horse weighing up to 1,250 pounds at the labeled dose of 91 mcg of ivermectin per pound of body weight, equivalent to 200 mcg/kg. Each plunger marking delivers enough paste for 250 pounds of body weight. Set and lock the ring at the prescribed marking, make sure your horse’s mouth contains no feed, and deposit the paste on the back of the tongue. Raising your horse’s head for a few seconds afterward helps support administration as directed on the label.
For your horse, those specifications mean the dose is tied to current body weight instead of a one-size-fits-all amount. The oral paste format keeps treatment straightforward in the barn aisle, while the labeled parasite and life-stage list lets you and your veterinarian see exactly what the dose is intended to control. Accurate weighing matters: the label cautions against underdosing because an incomplete dose may be ineffective and may encourage parasite resistance.
Zimecterin should be used as one part of a veterinarian-guided parasite program, not as a substitute for fecal testing or an automatically repeated calendar. The manufacturer advises horse owners to work with their veterinarian and selectively treat horses that need treatment. Store the syringe at 68°F to 77°F, with permitted excursions from 59°F to 86°F, and use it only for horses as labeled. Trusted since 1948, Schneiders helps you choose proven horse-care products with clear directions and practical barn-ready dosing.
Each 0.21 oz (6.08 g) syringe contains enough paste for one horse weighing up to 1,250 pounds at the labeled dose of 91 mcg of ivermectin per pound of body weight, equivalent to 200 mcg/kg. Each plunger marking delivers enough paste for 250 pounds of body weight. Set and lock the ring at the prescribed marking, make sure your horse’s mouth contains no feed, and deposit the paste on the back of the tongue. Raising your horse’s head for a few seconds afterward helps support administration as directed on the label.
For your horse, those specifications mean the dose is tied to current body weight instead of a one-size-fits-all amount. The oral paste format keeps treatment straightforward in the barn aisle, while the labeled parasite and life-stage list lets you and your veterinarian see exactly what the dose is intended to control. Accurate weighing matters: the label cautions against underdosing because an incomplete dose may be ineffective and may encourage parasite resistance.
Zimecterin should be used as one part of a veterinarian-guided parasite program, not as a substitute for fecal testing or an automatically repeated calendar. The manufacturer advises horse owners to work with their veterinarian and selectively treat horses that need treatment. Store the syringe at 68°F to 77°F, with permitted excursions from 59°F to 86°F, and use it only for horses as labeled. Trusted since 1948, Schneiders helps you choose proven horse-care products with clear directions and practical barn-ready dosing.
🛡️
Full-Spectrum Protection
Kills large and small strongyles, ascarids, bots, hairworms, lungworms, threadworms, and the organisms that cause summer sores — in one dose.
✅
Safe for Every Horse
Proven safe for foals, pregnant mares at any gestational stage, and breeding stallions without affecting fertility.
Side by Side
Compare the Label Before You Dose
A neutral, label-based comparison of three oral equine deworming pastes containing 1.87% ivermectin. Published similarities are shown directly, and information absent from a cited page is marked “Not listed.”
| Feature | Schneiders Zimecterin Paste 1.87% | DuraMectin Paste 1.87% | Farnam IverCare Paste 1.87% |
|---|---|---|---|
| Active ingredient | Ivermectin | Ivermectin | Ivermectin |
| Active-ingredient concentration | 1.87% | 1.87% | 1.87% |
| Product form and labeled route | Oral paste for horses | Oral paste for horses | Oral paste for horses |
| Maximum body weight treated per syringe | Up to 1,250 lb | Up to 1,250 lb | Up to 1,250 lb |
| Labeled dose rate | 91 mcg/lb (200 mcg/kg) | 91 mcg/lb (200 mcg/kg) | 91 mcg/lb (200 mcg/kg) |
| Body-weight amount per plunger marking | 250 lb | 250 lb | 250 lb |
| Bots included on published label or product page | Yes — oral and gastric stages are listed | Yes — oral and gastric stages are listed | Yes — bots are listed |
| Early or arterial Strongylus vulgaris stages included | Yes — early forms in blood vessels are listed | Yes — early forms in blood vessels are listed | Yes — arterial stages are listed |
| Published use for horses of all ages and pregnant mares | Yes — manufacturer identifies use for all ages, including pregnant mares | Yes — including mares at any stage of pregnancy | Yes — including mares at any stage of pregnancy |
| Net syringe contents on cited source | 0.21 oz (6.08 g) | 6.08 g | Not listed on the cited product page |
One Syringe. The Parasites That Matter Most. Gone.
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Get Full-Spectrum Parasite Control — One Dose Does It All
Zimecterin's 1.87% ivermectin formula clears bots, bloodworms, ascarids, and more in a single calibrated dose — the kind of comprehensive protection your horse's health depends on season after season. Schneiders has trusted this product for decades because it delivers exactly what it promises, with no compromises on safety or efficacy. Order today and build your horse's three-times-a-year protection plan on a foundation you can actually count on.
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