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:
Petit mal seizures:
Grand mal seizures occur in three stages:
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:
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:
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.