Horse Dewormer Dosage Calculator — Ivermectin, Moxidectin & More
Calculate the correct dewormer dose for your horse by weight. Supports the five most common equine anthelmintics.
Calculator
Targets
Large & small strongyles, bots, pinworms, ascarids, Habronema, threadworms
Once common, resistance in small strongyles widespread in young horses.
Frequently Asked Questions
How often should I deworm my horse?
The AAEP recommends fecal-egg-count-based deworming, not calendar deworming. Do FEC every 3–6 months; deworm only horses with > 200 eggs/gram. Overall, 2–4 strategic treatments per year is typical.
What is the correct ivermectin dose for horses?
0.2 mg per kg (roughly 91 mcg per lb). A standard ivermectin paste tube (1.87 %) covers a 1,250 lb horse. Use half a tube for a 625 lb pony.
What dewormer covers tapeworms?
Praziquantel — usually combined with ivermectin (Equimax, Zimecterin Gold) or moxidectin (Quest Plus). Deworm for tapeworms 1–2× per year, typically in autumn.
Can I give a horse too much dewormer?
Most dewormers have wide safety margins. Ivermectin overdose (>20×) can cause blindness or seizures, especially in foals or ill horses. Always weigh accurately.
What is resistance in horse parasites?
Many US horse farms now have small strongyle populations resistant to fenbendazole and pyrantel. Ivermectin + moxidectin still work for most, but are losing efficacy. Fecal egg counts confirm what's working on your farm.
Sources & References
- [1]AAEP Parasite Control Guidelines — American Association of Equine Practitioners
- [2]Plumb's Veterinary Drug Handbook — Plumb's Veterinary Drugs
- [3]
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