Seizure (Epilepsy) Symptoms in Dogs and Cats
The signs and symptoms of dog and cat seizures vary markedly. Although it's easy to recognize convulsive grand mal seizures, many do not recognize the signs of petit mal seizures. Signs can also be missed because many seizures occur while pets are resting or sleeping.
Grand mal seizures:
- Aura or period with anxiety, hiding, or attention seeking
- Convulsions with paddling, drooling, urinating, or defecating
- Recovery period with disorientation, aggression, hunger, or confusion
Petit mal seizures:
- Imaginary gum chewing, tail chasing, or flank sucking
Grand mal seizures occur in three stages:
- Before the seizure is the aura: a period of anxiety, hiding, or seeking attention
- During, or after the seizure (postictal phase): convulsing, falling down, paddling, urinating, and defecating
- After the seizure (postictal phase): disoriented, aggressive, hungry, and confused.
Cats that have grand mal seizures have more violent episodes than dogs with grand mal seizures.
Recovery during the postictal phase can take hours or days. Pets do not act like themselves during this period, and aggressive attacks may occur without provocation.
Cats and dogs with petit mal seizures are dazed or disoriented. They stare into space for a few seconds or a few minutes. Then, they act normal. Many pet guardians do not interpret these events as a seizure and may think their pet is having a "senior moment" or "spaced out." Dogs with petit mal seizures chew imaginary gum, snap at imaginary flies, gaze up at imaginary stars, chase their tails, or suck their flanks. Even when dogs engage in these activities, pet guardians may not realize their pet is having a seizure.
Cats may also display petit mal seizure activity that is difficult to recognize. For example, they may meow, drool, sit down, or run around as if crazed. The pupils in their eyes may change size rapidly by dilating and contracting (hippus). Cat owners may assume the signs are caused because their cat is psychotic, anxious, or has some form of behavior problem rather than realize their cat is having seizures.
Diagnosing the existence of seizures is easier than diagnosing the cause. The presence of seizures is clear if your pet has convulsions, and the presence of seizures is suspected if the pet has significant "spaced out" periods—with or without unusual behavior such as fly snapping. Of course, your veterinarian will confirm that the "spaced out" periods is not caused by brain hypoxia (low levels of oxygen) from respiratory or heart disease.
Diagnosing the cause of seizures can be difficult because:
- Many expensive tests can be necessary to determine the cause and many pet guardians cannot afford to have them done.
- We do not know enough about the brain to identify the cause of some seizures, so we say the disease is primary or idiopathic and assume it has a genetic cause.
Cats can develop a hyperesthesia (hyper = extremely and aesthesia = sensation) syndrome when an area along the back becomes so sensitive it is painful. This is also called "twitchy cat syndrome" and "neurodermatitis." If your cat has feline hyperesthesia syndrome, the muscles along your cat's back twitch or ripple, and your cat vocalizes as though in pain. Some cats lick imaginary skin, bite and harm themselves or become aggressive toward others. These behaviors may appear so similar to psychomotor or petit mal seizures that it is difficult to tell whether the problem is seizures or not. Some veterinarians believe these are truly behavior problems; others believe they are neurologic; still others believe this behavior is caused by flea bite sensitivity.
Tests used to diagnose seizures include the following:
- Neurologic exam that tests each of the 12 cranial nerves
- Electroencephalogram or EEG for brain wave irregularity
- Magnetic resonance imaging (MRI), and CAT scans for brain tumors, hemorrhage, or malformations
- Cerebral spinal fluid (CSF) analysis for infections, parasites, white blood cells (granulocytes), and toxins
- Routine blood tests to measure red blood cells, white blood cells, electrolytes (sodium, potassium, calcium and magnesium), liver function, kidney function, and thyroid levels
- Blood sent for identification of heavy metals and infectious agents
- Stomach contents sent for identification of heavy metals or poisonous plants
- X-rays to identify swallowed metal objects such as pennies
- Urine tests for ketones, crystals, specific gravity, and sugar
- Blood pressure for kidney disease, heart failure, or intracranial tumor
- EKG for cardiac disease that could cause lack of blood flow to the brain
In addition to all the laboratory tests, pet guardians are asked to keep a diary that tracks the phase of the moon, physical illnesses, activity, sleep depravation, stressful events, heat cycle, and medication dosages. If a seizure occurs, describe what happened before, during, and after the event and how long it lasted. A well-kept diary helps identify triggering events so that medications can be increased prior to these events.