Ivermectin horse paste is an over-the-counter equine dewormer sold in pre-filled oral syringes. In the United States the standard product is a 1.87% ivermectin gel in a 6.08 g (0.21 oz) syringe, calibrated to treat one horse weighing up to 1,250 pounds. It is approved by the FDA as an animal drug for horses, and the labeling on every brand states plainly that it is not for use in humans.

That distinction matters, because ivermectin for people is a separate, differently dosed product that is regulated differently from state to state. If your question is really about the human tablet rather than the equine gel, the rules on where human ivermectin can legally be bought have shifted in several states since 2025 and are covered separately. This page sticks to the veterinary paste: what is in it, how the syringe is calibrated for horses, what the warnings say, and what it typically costs at farm and pet retailers.

Key takeaways

  • US equine paste is a 1.87% ivermectin gel in a 6.08 g syringe; per the Durvet and Farnam labeling, one syringe treats a horse up to 1,250 lb at 91 mcg per pound (200 mcg/kg).
  • Each marking on the plunger delivers a dose for 250 lb of body weight, so accurate dosing depends on an accurate current weight.
  • Every label carries an animal-use-only warning. Farnam's Horse Health packaging states the product is not safe or approved for human use and that such use could cause severe injury or death.
  • It is stocked at farm-supply and pet retailers including Tractor Supply, Chewy, Jeffers and Murdoch's, typically without a prescription because it is an OTC animal drug.
  • State laws passed in 2025 that loosened access to ivermectin apply to human tablets dispensed by pharmacists — not to veterinary paste. Legal details in this article were last verified on September 26, 2026; retailer stock and prices change constantly and should be checked on the retailer's own page.

What ivermectin horse paste is and its concentration

Two identical unbranded equine paste syringes and a plain white carton laid out on a tack room shelf

Ivermectin paste is an antiparasitic (anthelmintic and boticide) gel for oral administration to horses. The active ingredient concentration is standardized across US brands at 1.87% ivermectin, packaged in a single-dose plastic syringe holding 6.08 grams of paste. Most are apple-flavored to improve palatability, which is why product pages from Chewy and Tractor Supply describe them as apple-flavored gels.

According to the VetOne Vetrimec listing at Tractor Supply, the paste is indicated for treatment and control of large and small strongyles, pinworms, ascarids, hairworms, large-mouth stomach worms, bots, lungworms and intestinal threadworms, along with summer sores caused by Habronema and Draschia spp. and dermatitis caused by Onchocerca sp. Farnam's equine paste labeling describes activity against 35 species and stages of worms and bots combined, including all three larval stages of the two most common bot species.

Common brands

The formulation is the same strength regardless of label. Widely sold names include Durvet Ivermectin Paste, Dechra Ivermectin Dewormer Paste, Zimecterin, Farnam Horse Health Equine Ivermectin Paste and VetOne Vetrimec. Marketplace sellers on Amazon also list generic 1.87% syringes. Because the concentration is identical, brand choice generally comes down to price, flavor and availability rather than potency.

Approved age and reproductive status

Label language from DailyMed for ivermectin paste 1.87% states it may be used in horses of all ages, including mares at any stage of pregnancy, and that stallions may be treated without adversely affecting fertility. Tractor Supply's Vetrimec page notes approval for all horses over six weeks of age. As with any animal drug, your veterinarian is the appropriate source for decisions about foals, sick animals or horses on other medications.

How the dosing syringe works (weight-based)

Close-up of fingers sliding the dose ring along the barrel of a weight-marked equine paste syringe next to a weight tape

The syringe is the dosing device. Per the Durvet directions reproduced by Jeffers, one syringe contains enough paste to treat a single 1,250 lb horse at the labeled rate of 91 mcg ivermectin per pound of body weight (200 mcg/kg), and each weight marking on the plunger delivers enough paste to treat 250 lb of body weight. The barrel has a movable ring or collar that you set against the marking matching the horse's weight, so the plunger stops at the correct volume.

Horse body weight Plunger markings used Approximate share of one 6.08 g syringe
250 lb 1 marking One-fifth
500 lb 2 markings Two-fifths
750 lb 3 markings Three-fifths
1,000 lb 4 markings Four-fifths
1,250 lb 5 markings Full syringe

Why weight accuracy matters

The Durvet directions warn explicitly not to underdose, stating that each animal should receive a complete dose based on a current body weight, and that underdosing may result in ineffective treatment and encourage the development of parasite resistance. A weight tape or livestock scale is more reliable than an eyeball estimate. Horses above 1,250 lb need a second syringe or a larger product, and a veterinarian should advise on how to cover the extra weight.

Administration basics

The labeled route is oral. Standard practice described on manufacturer directions is to make sure the mouth contains no feed, insert the syringe tip into the corner of the mouth at the interdental space, deposit the paste on the back of the tongue and raise the head briefly so the horse swallows rather than spits. Deworming programs, including whether and how often ivermectin is used, should be based on fecal egg counts and veterinary advice rather than a fixed calendar.

Safety warnings: labeled for animal use only

A handler's hands guiding a paste syringe toward the corner of a bay horse's mouth during deworming

Ivermectin horse paste is labeled for animal use only and is not approved for people. The DailyMed label for DuraMectin ivermectin paste 1.87% carries the warnings: do not use in horses intended for human consumption; not for use in humans; keep this and all drugs out of reach of children; refrain from smoking and eating when handling; wash hands after use; avoid contact with eyes. Farnam's Horse Health packaging, as reproduced by the retailer Murdoch's, goes further, stating the product is not safe or approved for human use and that such use could cause severe personal injury or death.

Independent reviews of the question reach the same conclusion. A 2025 fact-check published by Factually summarized manufacturer positions that equine paste is not approved for use in humans, noting these products are formulated, dosed, flavored and packaged for horses and have not been tested in human trials. A separate December 2025 review noted that use of animal ivermectin products — particularly high-concentration pastes and injectables — has been linked to reported poisonings and cases of neurotoxicity, and that the FDA has emphasized animal formulations are different products from those approved for people.

Practical handling precautions

  • Store the syringe out of reach of children and away from food; apple flavoring makes accidental ingestion more plausible, not less.
  • Wash hands after dosing and avoid eye contact, as the labeling directs.
  • Do not treat other species with an equine product on your own judgment. Species differences are real — dogs of certain breeds are notably sensitive, which is why ivermectin use in dogs is a separate topic, ivermectin dosing in cats is another, and cattle products such as pour-on ivermectin for cattle are formulated for topical rather than oral use.
  • Durvet's precautions state the product is for application in horses only and that administration to other species may cause adverse reactions.

A note on state ivermectin laws

Several states changed access rules for human ivermectin in 2025. Pharmacy Times reported on July 10, 2025 that four states had passed laws allowing over-the-counter sale, and described Louisiana's SB 19 / Act 464, effective June 20, 2025, as permitting pharmacists to dispense ivermectin to adults under a standing order, with a screening risk-assessment tool and counseling on indications and contraindications. That count predates Texas, whose HB 25 took effect December 4, 2025, bringing the total to five: Tennessee (first, in 2022), Arkansas, Idaho, Louisiana and Texas. Bills filed in other states did not become law. Georgia's SB 366 (2025) would have removed ivermectin from that state's dangerous-drug list, but it never advanced out of committee; a narrower 2026 measure, SB 440, passed the Georgia House and was never taken up by the Senate before the session adjourned on April 2, 2026. Mississippi's SB 2541 (2026) died when that state's regular session adjourned in April 2026 without an ivermectin law. Florida's HB 29 was withdrawn before introduction in the 2026 session, and measures filed in Missouri (SB 1086) and South Carolina (H. 3916 / H. 4042) were not enacted either. None of these laws change the status of veterinary paste, which remains an animal drug labeled for horses. Confirm current status with your state legislature or board of pharmacy; the legal details here were last verified on September 26, 2026.

Where to buy it (farm stores and online)

A farm store receipt, coins and an unbranded equine paste syringe side by side on a wooden counter

As an OTC animal drug, 1.87% equine paste is sold without a prescription at farm, ranch and pet retailers. Retailers that list it include Tractor Supply (Durvet, Dechra, Zimecterin and VetOne Vetrimec), Chewy (Durvet), Jeffers (Durvet), Murdoch's (Farnam Horse Health) and Amazon marketplace sellers. Regional feed stores, tack shops, veterinary clinics and equine catalog suppliers typically carry at least one brand as well.

What to check at the point of sale

  • Concentration and fill weight: 1.87% ivermectin, 6.08 g, one syringe per 1,250 lb horse.
  • Expiration date and seal: buy from established retailers; the DailyMed label specifies storage at 68–77°F, with excursions between 59–86°F permitted.
  • Single ingredient vs. combination: some equine products pair ivermectin with praziquantel for tapeworms, which is a different label and a different dose.
  • Quantity: multi-syringe packs are common for multi-horse barns; single syringes suit one animal.

Availability varies seasonally and by region, and online listings change.

Typical price

Ivermectin paste is among the least expensive equine dewormers, largely because the molecule is long off-patent and several manufacturers compete on identical strength. Single 6.08 g syringes are usually the cheapest single-dose dewormer on the shelf, and per-syringe cost generally drops in multi-packs of six or twelve.

We could not verify one national price: Tractor Supply, Chewy, Jeffers, Murdoch's and Amazon each price these syringes individually, and those figures change with promotions, brand and region. Rather than quote a number that may be stale by the time you read this, check the current listing on the retailer's own product page for the specific brand and pack size on the day you buy.

What drives the price difference

  • Pack size: six- and twelve-count boxes lower the per-dose cost.
  • Brand: Zimecterin and Farnam typically list above generic Durvet or Dechra syringes despite the same 1.87% strength.
  • Combination products: ivermectin-plus-praziquantel pastes cost more than ivermectin alone.
  • Shipping: a single low-cost syringe ordered online can cost more delivered than bought in store.

Frequently asked questions

Can people take ivermectin horse paste?

No. It is labeled for animal use only and is not approved for people. Manufacturer labeling states it is not for use in humans, and Farnam's packaging warns that human use could cause severe personal injury or death. Ivermectin for humans is a separate prescription product with its own approved indications and dosing; a licensed clinician and pharmacist are the appropriate route.

How much paste does a 1,000 lb horse get?

Four of the five weight markings on the plunger, since each marking covers 250 lb, per the Durvet directions. Use the horse's current weight, not a guess.

Does ivermectin horse paste need a prescription?

Generally no. It is sold as an OTC animal drug at farm and pet retailers in the US. State laws on non-prescription ivermectin apply to human tablets dispensed through pharmacies, not to this veterinary product.

Is the apple-flavored version different in strength?

No. Flavoring affects palatability only; the apple and unflavored versions listed by retailers are both 1.87% ivermectin in a 6.08 g syringe.

What parasites does it not cover?

Ivermectin alone is not labeled for equine tapeworms; products combining ivermectin with praziquantel address those. Resistance patterns also vary by farm, which is why the American Association of Equine Practitioners and most veterinarians recommend fecal egg count testing to guide deworming rather than routine dosing.

Can it be used in pregnant mares?

The DailyMed labeling states ivermectin paste 1.87% may be used in horses of all ages, including mares at any stage of pregnancy, and that treating stallions does not adversely affect fertility. Confirm with your veterinarian for any individual animal.

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