How does dosage for ivermectin horse paste compare to approved human ivermectin doses?
Executive summary
Human oral ivermectin for approved parasitic uses is typically a single dose of about 150–200 micrograms per kilogram (0.15–0.20 mg/kg) of body weight (Mayo Clinic) [1]. Common equine ivermectin paste is labeled at about 200 micrograms per kilogram as well (91 µg per lb ≈ 200 µg/kg), but the paste is formulated for horses, contains much larger total milligram amounts per syringe, and is not tested or approved for humans [2] [3].
1. Same micrograms-per-kilogram number — different framing, different risks
On a per‑kilogram basis, many horse ivermectin pastes and human tablets are expressed around the same target: ~200 micrograms per kilogram (0.2 mg/kg). Manufacturer labeling for equine paste lists 91 micrograms per pound, which converts to roughly 200 µg/kg [2]. Human dosing information (for approved parasitic uses) also commonly cites about 200 µg/kg as a single dose [1]. Those identical numbers can give a misleading impression of interchangeability; available sources stress that the formulations, packaging, and total drug quantities differ and that veterinary products are not approved for human use [3] [2].
2. Total milligrams in a horse syringe can vastly exceed a single human tablet
A syringe of horse paste is made to dose animals that weigh hundreds to over a thousand pounds. That means the syringe contains many milligrams of ivermectin intended to be divided according to animal weight; a single human of 70 kg taking 0.2 mg/kg would need about 14 mg total, whereas a horse syringe may contain tens or even hundreds of milligrams to treat a 1,000+ lb animal [2]. The larger total quantity in the container increases the practical risk of accidental overdose when people attempt to self‑measure.
3. Inactive ingredients and formulation differences matter — safety and testing
Manufacturers explicitly warn that equine ivermectin paste “has not been tested in humans and is not approved for use with humans” [3]. Veterinary formulations include inactive ingredients, flavorings, and manufacturing standards intended for animals; those excipients can have unknown effects in people [3]. WebMD underscores that taking a dose meant for a large animal can be toxic or deadly to a person and that veterinary products aren’t designed with human safety testing in mind [4].
4. Clinical context: approved human uses vs. unproven COVID claims
Human ivermectin tablets are FDA‑approved for specific parasitic infections at listed doses, and agencies say there is no authorization to use ivermectin for COVID‑19 prevention or treatment [5]. Medical reporting notes there is no approved human ivermectin dosage for COVID‑19 [6]. Some clinical studies have tested different regimens (for example, trials in Bangladesh used 12 mg daily for 5 days in a research setting), but regulators and mainstream reviews do not endorse routine use for COVID‑19 [7] [6] [5].
5. Toxicity thresholds and the illusion of a wide safety margin
Summaries of toxicology note that the FDA‑approved single dose for humans (0.15–0.20 mg/kg) is far below the LD50 ranges estimated from animal studies, but achieving plasma levels that inhibited SARS‑CoV‑2 in vitro would require doses many times higher — an amount considered consistent with poisoning [8]. The FDA warns that taking large doses can be dangerous and that veterinary products are not a safe substitute for human medications [5]. WebMD also warns of severe risks from animal‑grade dosing intended for multi‑hundred‑kilogram animals [4].
6. Why people still use horse paste — access, cost, and misinformation
First‑person and cultural reporting documents how some people sought cheaper or easier access to ivermectin through horse paste, driven by online videos and perceived difficulty obtaining human pills [9]. Commercial and advocacy sites market “human‑grade” alternatives and frame veterinary paste as risky, highlighting an implicit agenda to sell safer human formulations [10].
7. Bottom line and practical advice from sources
Sources converge on two points: human ivermectin dosing for approved parasitic diseases is weight‑based at ~150–200 µg/kg [1], and veterinary ivermectin paste is not tested or approved for humans and poses dosing and formulation risks despite similar µg/kg labels [3] [2] [4]. The FDA and mainstream medical sources explicitly warn against using animal ivermectin for COVID‑19 or self‑treating with livestock products [5] [6].
Limitations: available sources do not provide an exhaustive list of inactive ingredients across all horse‑paste brands or a standardized milligram count per syringe for every product; specific overdose case rates from horse‑paste misuse are not detailed in these results (not found in current reporting).