Specializing in Canine and Feline Neurology and Neurosurgery for over 35 years


Seizure disorders are common and there are many causes. The most common cause of seizures in dogs between one and five years of age is primary (idiopathic) epilepsy. Primary epilepsy is generally treated with various anticonvulsant medications. Although not always required, a complete seizure workup may be recommended and could include: bloodwork to screen for metabolic or infectious causes, brain imaging (MRI) to search for structural problems, and analysis of cerebrospinal fluid (CSF) for signs of inflammation.

A seizure is composed of three phases: preictal, ictus, and postictal; not every seizure includes all three phases. Thorough description (e.g. video) of a possible seizure can help the veterinarian determine the type of seizure and how it can best be treated.

Pets thought to have seizures should be examined by a veterinarian as soon as possible. The condition of rapidly recurring seizures without recovery between episodes is called status epilepticus and is considered a serious medical emergency.

COMMON SIGNS (Episodic and Stereotyped):

  • sudden/violent shaking
  • paddling
  • vocalization
  • dilation of pupils
  • unresponsive/staring
  • loss of consciousness
  • salivating/drooling
  • stiffness
  • twitching
  • involuntary urination/defecation


  • Congenital
    • hydrocephalus
    • lissencephaly
  • Inflammatory
    • Infectious
      • bacterial
      • rickettsial
        • Rocky Mountain spotted fever
        • ehrlichiosis
      • viral
        • distemper
        • feline infectious peritonitis (FIP)
        • feline immunodeficiency virius (FIV)
        • feline leukemia virus (FeLV)
      • fungal
        • cryptococcosis
      • protozoal
        • neosporosis
        • toxoplasmosis
      • parasitic
    • Immune-Mediated
      • meningoencephalitis
      • breed-specific encephalitis
        • small dog encephalitis
        • pug dog encephalitis (PDE)
  • Neoplastic
    • glioma
    • meningioma
    • metastatic neoplasias, e.g lymphoma, hemangiosarcoma, adenocarcinoma, melanoma
  • Toxic
    • strychnine
    • metaldehyde
    • organophosphate
    • heavy metals
  • Traumatic
    • head injury
  • Metabolic
    • storage diseases
    • thiamine deficiency
    • hypocalcemia
    • hypoglycemia
    • hepatoencephalopathy
      • portosystemic shunt
      • hepatic microvascular dysplasia
      • liver failure/hepatitis
  • idiopathic
    • epilepsy