While early intervention is critical to stopping EPM from causing further nerve damage, a rush to treatment can result in lost recovery time—not to mention lost money. Several diseases masquerade as EPM, causing similar neurologic signs. Yet, EPM treatments are only effective against EPM. That’s why it’s critical to work with a veterinarian to confirm an EPM diagnosis before treatment.
Diagnostic Shortcuts Shortchange the Horse
When EPM is suspected, the crucial first step is for veterinarians to perform a thorough physical and neurologic examination. This allows them to rule out certain conditions. Even though some diseases pose as EPM—and vice versa—veterinarians can look for telltale characteristics of specific diseases to help avoid unnecessary testing for not only for EPM but also other conditions.
After homing in on EPM as a possibility, veterinarians then begin a more specific diagnostic process. This involves antibody testing to determine if there’s evidence of a central nervous system infection in the horse.
Diagnostics, especially those for EPM, is money well spent because you aren’t paying for unneeded tests and treatments. But the biggest payoff is better horse health. Appropriate diagnostics help ensure the horse is being treated for the correct disease. The sooner a horse receives appropriate treatment, the better the outcome.
EPM Treatment and Prevention
If the veterinarian diagnoses EPM, fortunately there are FDA-approved EPM treatment products available. Horses treated with an anticoccidial drug, such as PROTAZIL® (1.56% diclazuril) Antiprotozoal Pellets, are 10 times more likely to improve than untreated horses.¹ PROTAZIL® is the only FDA-approved product that comes in a convenient top-dress formula administered on the daily feed ration.
The very best outcome would be to prevent horses from contracting EPM in the first place. Although the veterinary community is researching preventative strategies, for now, the best way to keep horses from getting EPM is to avoid exposing them to opossum feces. The horse ingests the infective organism found in opossum scat while eating or drinking contaminated feed or water. Despite best efforts, keeping opossums off the farm is difficult. Maintaining a clean barn and property makes the farm less attractive to opossums.
From diagnosis to treatment, the veterinarian is a horse owner’s best EPM resource. If you are concerned about EPM or think your horse might be showing neurological signs, call your veterinarian immediately.
Important Safety Information
Use of Protazil® (1.56% diclazuril) is contraindicated in horses with known hypersensitivity to diclazuril. Safe use in horses used for breeding purposes, during pregnancy, or in lactating mares has not been evaluated. The safety of Protazil® (1.56% diclazuril) with concomitant therapies in horses has not been evaluated. For use in horses only. Do not use in horses intended for human consumption. Not for human use. Keep out of reach of children.
 Reed SM, et al. Equine Protozoal Myeloencephalitis: An Updated Consensus Statement with a Focus on Parasite Biology, Diagnosis, Treatment and Prevention. J Vet Intern Med 2016;30:491–502.