SMART Worming: A Smarter Approach to Equine Parasite Control
Author - Dr. James Carrier BVSc MSc MRCVS is a veterinary adviser with Boehringer Ingelheim Animal Health, based in the North of England. His interests include infectious disease, sustainable medicine, and science communication. James spent ten years in private equine practice before competing an MSc in One Health & Infectious Disease, joining the Boehringer team in 2024.
James says: A smarter approach to parasite control is essential if we are to prolong the usefulness of the drugs on which we depend, keep our horses healthy and protect our environment.
Paid Partnership
This article has been produced in partnership with Boehringer Ingelheim Animal Health UK to raise awareness of sustainable parasite control and responsible worming practices in horses.
For years, deworming was one of the most routine parts of horse care. Buy a dewormer, stick to a schedule, rotate brands every few months, and repeat across the whole yard. It felt practical and proactive.
But parasite control has moved on.
Today we know far more about how worms behave, how resistance develops, and how our deworming habits directly affect the long-term health of our horses. This has led to a shift away from blanket, routine deworming, and towards a more targeted, evidence-based approach.
Why Has Horse Worming Changed?
Dewormer resistance is no longer a theoretical concern. It is real, increasingly widespread, and affecting horses across the UK. Parasites are adapting to the products we have relied on for decades.
Although there may seem to be a wide range of dewormers available, they are all based on just five main classes of active ingredients, and for now there are no new ones waiting to replace them.
Once resistance develops, our options become increasingly limited.
The Main Active Ingredients Used in Horse Wormers
The five main active ingredients used to treat worms in horses include:
- Fenbendazole, ivermectin, moxidectin and pyrantel, which target worms such as redworms, roundworms and pinworms.
- Praziquantel, which is effective against tapeworms and is only available in combination with ivermectin or moxidectin.
- Pyrantel can also treat tapeworms when given at a double dose.
Protecting the effectiveness of these products is essential.
Which Equine Worms Present the Greatest Risk?
Not all worms pose the same level of threat, and not every horse faces the same risks. In adult horses the primary parasites of concern are:
- Small and large redworms
- Roundworms (mainly in foals and youngsters)
- Tapeworms
This is why evidence-based deworming, guided by testing, is now widely recommended.
The Role of Faecal Egg Counts (FECs)
Faecal Egg Counts (FECs) are a key part of this approach. They show which horses are actively shedding eggs and which aren’t.
Why One Worming Approach Doesn't Fit Every Horse
Different worms respond to different products, and resistance patterns vary between species. This means that choosing the right dewormer matters just as much as choosing whether to deworm at all.
Understanding the SMART Worming Principle
Sustainable parasite control isn’t about doing nothing; it is about making informed choices.
What Does SMART Worming Involve?
The SMART Worming principle combines:
- Regular risk assessments
- Evidence-led testing such as faecal egg counting (FECs)
- Advice on the appropriate, targeted treatment
- Advice on good pasture management
Factors such as age, grazing habits, stocking density, exposure to new horses, and previous test results all influence a horse’s parasite risk.
Download the SMART Worming Schedule
The SMART Worming schedule provides a clear, practical framework for assessing risk and planning treatments throughout the year. You can find it here:
An educational service from the makers of Eqvalan® Oral Paste for Horses and Eqvalan Duo® Oral Paste (UK only).
Further information is available in the SPC or from Boehringer Ingelheim Animal Health UK Ltd, RG12 8YS, UK.
©2026. All rights reserved. Date of preparation: Apr 2026. UI-EQU-0064-2026. Use Medicines Responsibly.
This post is an opinion and should only be used as a guide. You should thoroughly discuss any change to your pet’s care or lifestyle with your vet before starting any program or treatment. We update content regularly to reflect the latest pet health standards.
