How Often Should You Worm a Horse in Australia? (+ How to Choose the Best Wormer)
2nd Nov 2026
Vets now recommend worming based on faecal egg counts (FECs) and your horse's risk, with no fixed calendar. For most healthy adult horses, that works out to one to two treatments a year, with extra treatments for high egg shedders and more frequent treatment for foals and young horses. There is no single best wormer. The right choice depends on the worms present, the season and resistance on your property.
Why the Old "Worm Every 6–8 Weeks" Approach No Longer Works
Worming every 6–8 weeks was once standard advice. Treating every horse on a fixed schedule means worms meet the same drugs again and again, and the survivors pass on their resistance. Small strongyles (redworms) and ascarids (large roundworms) are now increasingly resistant to wormers, and the level varies between properties, even in the same region.
Strategic worming is the current approach. A FEC counts the parasite eggs in each gram of manure (eggs per gram, or EPG), which tells you exactly which horses need a wormer and keeps the rest of your herd off unnecessary treatments.
How Often Should You Worm a Horse in Australia?
Most healthy adult horses need one to two treatments a year, and FEC results guide any extras.
Adult Horses: Low, Moderate and High Shedders
- Low (under 200 EPG): No extra treatment needed.
- Moderate (200–500 EPG): A standard treatment is recommended.
- High (over 500 EPG): Consider one to two extra treatments through the grazing season, and up to four a year for some horses.
Retest 2 weeks after the wormer's egg reappearance period (the time it takes for eggs to show up in manure again).
Foals and Young Horses
Foals need at least four treatments in their first year. These start at about 2 months, with an extra dose before weaning if more than 3 months have passed since the last one, then at 9 months (including tapeworm cover) and at 12 months.
Yearlings and two-year-olds are treated as high shedders, with about three treatments a year. Move weaned foals onto the cleanest paddock you have.
Seasonal Worming in Australia: What to Target When
- Spring and autumn: These are the peak transmission seasons, so time treatments then.
- Redworms (small strongyles): The most common worms in horses. Their young can burrow into the gut wall and lie dormant, and they become active again in spring. Ask your vet about a targeted treatment.
- Tapeworm: Give one properly timed treatment a year in late autumn or winter. A FEC can miss tapeworm, so a negative count does not rule it out.
- Bots: Treatments once to twice a year cover stomach bots and bloodworms.
New Arrivals
Quarantine new horses for at least 3–5 days, collect their manure and dispose of it away from your paddocks. Treat on arrival with a wormer your vet recommends, then run a FEC.
What's the Best Horse Wormer in Australia?
The best horse wormer in Australia is the one that works against the worms your horse actually has. Here’s a breakdown of our range of horse wormers:
| Wormer | Active Ingredients | Drug Class | Tapeworm | Bots | Best Used When |
|---|---|---|---|---|---|
| iMEC with Tape | Ivermectin, praziquantel | Macrocyclic lactone, tapewormer | Yes | Yes | Tapeworm and bot cover is due |
| Equest Gel Plus Tape | Moxidectin, praziquantel | Macrocyclic lactone, tapewormer | Yes | Yes | High shedders with suspected encysted small strongyles |
| Easymec | Ivermectin | Macrocyclic lactone | Not listed | Yes | Granules suit your horse and no tapeworm cover is due |
| Equigel with Tape | Moxidectin, praziquantel | Macrocyclic lactone, tapewormer | Yes | Yes | One dose should cover strongyles, tapeworm and bots |
| AppleMax Gold | Ivermectin, praziquantel | Macrocyclic lactone, tapewormer | Yes | Yes | You prefer a liquid with tapeworm and bot cover |
| Equimax Elevation Paste | Ivermectin, praziquantel, pyrantel | Macrocyclic lactone, tapewormer, tetrahydropyrimidine | Yes | Yes | Young horses need broad cover (labelled from 6 weeks) |
| Equimax Worming Paste | Abamectin, praziquantel | Macrocyclic lactone, tapewormer | Yes | Yes | Tapeworm and bot cover is due, including pregnant mares |
| Ammo Allwormer Paste | Abamectin, morantel | Macrocyclic lactone, tetrahydropyrimidine | Yes | Yes | Foals over 4 weeks or pregnant mares need treating |
| Strategy T | Oxfendazole, pyrantel | Benzimidazole, tetrahydropyrimidine | Aids control | Not listed | Foals and young horses, or ascarids resistant to mectins |
To choose, start with your FEC and your vet's advice. Check the label for age and breeding limits, ensuring it suits your horse’s needs. If tapeworm cover is due, pick a product containing praziquantel.
Your vet can run a faecal egg count reduction test to check your wormer still works, because resistance differs from one paddock to the next.
Drug Resistance: Why It Matters
Resistance develops when worms survive treatment and breed. Overuse and under-dosing both help resistant worms survive, and underestimating bodyweight is a common cause of under-dosing. Ascarids are commonly resistant to macrocyclic lactones, so a wormer that worked years ago may not work today.
A faecal egg count reduction test (FECRT) checks this. Your vet takes a FEC when you worm and another 14 days later. For an effective wormer, the count should fall close to 100%. Vets suggest repeating the test every 2–3 years. Rather than a rotating wormer schedule, let your test results guide your choice.
How to Worm Your Horse Correctly
- Dose by actual bodyweight, using a weight tape or scales.
- Check that your horse has swallowed the paste.
- Treat paddock mates together to stop them from reinfecting each other.
- Manage the pasture: remove manure every 24–72 hours, avoid overstocking and spell paddocks.
- Keep records with the date, product and FEC result each time, so your vet can spot trends.
If your horse shows signs of abdominal pain, read our guide to colic in horses and call your vet.
Book a Faecal Egg Count with Scone Equine
Our vets can arrange a FEC and a reduction test, and help you build a worming plan for your property. Contact our vets to get started.
FAQs
What's the best horse wormer in Australia?
No single wormer is best for every horse. The best choice works against the worms your horse has and suits its age and breeding status. A FEC and reduction test, plus your vet's advice, can point you to the right one.
How often should I worm my horse in Australia?
Healthy adults usually need one to two treatments a year, with extras for high shedders. Foals need at least four in their first year, and yearlings and two-year-olds about three a year.
What is a faecal egg count and how often should I do one?
An FEC estimates the number of parasite eggs per gram of manure. To learn your horse's pattern, test three times across spring and autumn, then repeat as your vet advises.
Can I worm a pregnant mare?
Yes, with a product labelled for pregnant mares. Equimax Worming Paste, Equest Gel Plus Tape, Equimax Elevation Paste, Ammo Allwormer Paste and Strategy T state this. Check the label of any other wormer or ask our vets.