What is the typical ivermectin dose for horses in mg/kg and common formulations?

Executive summary — clear clinical bottom line up front

The established, widely cited therapeutic dose of ivermectin for horses is 200 micrograms per kilogram of body weight, commonly expressed as 0.2 mg/kg or 91 micrograms per pound; this dose appears repeatedly in regulatory labels and product literature ^{[1] [2]}. Commercial equine products use that dose as the standard unit of administration across formulations, and manufacturers provide syringes, pastes, and liquids designed to deliver the same 0.2 mg/kg dosing when used per label instructions ^{[2] [3] [4]}. Recent product pages and labels from 2022 through 2025 restate the same numeric dose while describing different presentation forms and concentration units that owners and clinicians must translate correctly before dosing ^{[2] [3] [4]}.

1. Why the 0.2 mg/kg number dominates the field — regulatory and clinical consistency

Regulatory approvals and clinical reviews converge on 200 µg/kg (0.2 mg/kg) because that dose was the basis of pivotal efficacy and safety studies supporting market authorization; the DailyMed label for an ivermectin paste explicitly lists 91 mcg per pound (which equals 200 µg/kg) and a syringe fill targeted to treat a 1,250 lb horse at that rate ^[2]. Academic and therapeutic reviews summarize ivermectin pharmacology and licensed uses in animals and humans, and they continue to reference the same 0.2 mg/kg figure as the standard equine therapeutic dose ^{[5] [6]}. This uniformity across sources reduces confusion, but it requires careful weight estimation and correct product selection to ensure a horse actually receives 0.2 mg/kg, because concentration labels differ between pastes and liquids and between international product formulations ^{[2] [4]}.

2. How formulations differ — paste syringes, ready-to-use liquids, and concentration math

Manufacturers present ivermectin for horses in several common formats: oral paste syringes, ready-to-use liquid solutions, and occasionally flavored or compounded pastes; each format specifies concentration differently. The FDA-labeled ivermectin paste is described by mcg per lb and by syringe fill volume intended for a 1,250 lb animal, making on-syringe dosing straightforward if the user matches the horse to the labeled weight band ^[2]. A Canadian product listing for ivermectin liquid states a concentration of 10 mg ivermectin per mL, requiring a clinician to calculate milliliters per kilogram to achieve the 0.2 mg/kg dose—this translates to 0.02 mL/kg for a 10 mg/mL solution ^[4]. Bimectin flavoured oral paste marketed in 2025 reiterates oral paste use at 0.2 mg/kg, demonstrating consistent labeling across new product entries ^[3].

3. Practical dosing translation — common pitfalls and arithmetic checks clinicians must do

Translating label numbers into an accurate dose requires converting units and matching the product’s concentration to the horse’s weight; for example, 0.2 mg/kg equals 200 µg/kg, which equals 91 µg/lb — a conversion frequently printed on paste labels but not always on liquid vials ^{[1] [2]}. When a liquid lists milligrams per milliliter, the clinician must compute volume per kilogram: for a 10 mg/mL liquid, the correct volume is 0.02 mL per kg to deliver 0.2 mg/kg ^[4]. Errors arise when weight is estimated poorly, when owners give human ivermectin products (wrong formulations and doses), or when people misread mcg versus mg, so the combination of a clear label plus a brief unit check is essential to ensure the marketed dose equals the intended 0.2 mg/kg ^{[2] [4]}.

4. Evidence landscape and recent product entries — agreement, novelty, and what’s new

Sources from 2022 through 2025 show strong agreement on the 0.2 mg/kg standard: the FDA paste label ^[7] and multiple product descriptions including a 2025 Bimectin paste page and a 2025 Canadian liquid listing all restate the same dose while offering different delivery formats ^{[2] [3] [4]}. Scholarly reviews on ivermectin’s antiparasitic activity place the equine dose within the broader therapeutic context of ivermectin use across species and diseases, explaining mechanism and spectrum but not altering the horse dose recommendation ^{[6] [5]}. The recent product pages add convenience features—flavoring, ready-to-use liquid—but do not change the 0.2 mg/kg efficacy benchmark; they underscore the need to follow specific product directions to achieve that benchmark ^{[3] [4]}.

5. Final practical guidance — translating facts into safe use at the barn

To apply these facts safely: weigh or accurately estimate your horse, pick a veterinary-labeled equine product, and use the label math to deliver 0.2 mg/kg—paste syringes are often pre-dosed by weight band (91 µg/lb equivalents) whereas liquids require calculation of mL/kg based on mg/mL concentration ^{[2] [4]}. Manufacturers’ labels and regulatory documents from 2022–2025 consistently present the same numeric dose and should be the primary dosing reference for each specific product ^{[2] [3] [4]}. If there is any uncertainty, consult a veterinarian rather than improvising, because correct conversion and product-specific instructions are essential to deliver the standard 0.2 mg/kg therapeutic dose safely ^[2].