The diagnostic workup for seizures in adult horses begins with classifying the episode as a reactive seizure, structural epilepsy, or primary epilepsy, using signalment, neurologic examination findings, and targeted diagnostics to guide the pathway.Topics in Compa…
Electroencephalography (EEG) is a validated diagnostic tool for equine epilepsy, with recordings obtained under general anesthesia documented in horses across multiple studies.Journal of Vete… General anesthesia is a significant limitation for EEG interpretation, however, as it precludes assessment of cerebrocortical activity during arousal and sleep states essential for characterizing epileptic disorders, may obliterate paroxysmal discharges that support the diagnosis, and can cause burst suppression depending on the anesthetic agent used.Journal of Vete… Standing sedation with sublingual detomidine hydrochloride has been evaluated as an alternative approach, allowing EEG recording during slow-wave sleep (SWS), which facilitates detection of epileptic discharges.Journal of Vete…
SWS induced by detomidine reliably produces second-degree atrioventricular (AV) block, which is a normal finding during this sleep state in horses and should not be interpreted as a pathologic cardiac event.Journal of Vete… Decreased heart rate and respiratory rate accompany this state and are expected.Journal of Vete… Sleep facilitates epileptic activity, and paroxysmal discharges supporting an epilepsy diagnosis are most likely to appear during SWS.Journal of Vete…
A normal EEG does not rule out epilepsy. The absence of epileptic discharges during a recording is a recognized limitation of EEG in all species.Journal of Vete…+1
For emergency management of active seizures in adult horses, diazepam is the first-line drug. The Merck Veterinary Manual identifies diazepam as the most commonly used drug for seizures and status epilepticus in horses; specific dosing is referenced to disease-specific chapters rather than a single universal protocol.MSD Vet Manuals
Seizure classification in horses follows the same foundational framework used in small animals and dogs: an epileptic seizure is defined as a transient occurrence of signs due to abnormal, excessive, or synchronous neuronal activity in the brain, and epilepsy is defined as an enduring predisposition to generate epileptic seizures, practically applied as two or more unprovoked seizures at least 24 hours apart.BMC Veterinary… Patients who do not meet criteria for primary epilepsy but have no identifiable structural or reactive cause are classified as unknown epilepsy.Topics in Compa…
The veterinary literature contains limited information on equine epilepsy etiology, long-term treatment protocols, and outcome, reflecting the lower reported occurrence of seizures and epilepsy in equids compared to other species.Journal of Vete…
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