A seizure is a fit of abnormal neuromuscular activity caused by abnormal electrical activity in the brain. These episodes can range in severity from moments of mental blankness to minor muscle twitching or convulsions, to a full “grand mal” episode. “Grand mal” episodes are characterized by recumbency, paddling, drooling, urination, defecation, and altered consciousness.
There are a variety of causes of seizures in dogs. These include problems originating inside the brain and conditions outside the brain that trigger or predispose to abnormal brain activity. Seizures caused by conditions outside the brain can happen to dogs of any age. These include head trauma, infections, medication reactions, toxic substances, low blood sugar, derangements in blood electrolytes, liver or severe kidney failure, and deficiencies in oxygen or blood flow to the brain. Routine bloodwork to rule out these conditions is an essential first step in diagnostic work-up.
Dogs whose onset of seizures begin earlier than 6 months old are at greater risk of having been born with brain abnormalities or liver abnormalities. Dogs whose onset of seizures begin older than 6 years of age are also at greater risk of structural brain disease, particularly brain tumors. Dogs whose onset of seizures begin between 6 months and 6 years with no underlying cause identified by routine diagnostics often have idiopathic epilepsy, meaning that no cause can be found. Advanced imaging such a MRI or CT scan of the brain is then necessary to definitively diagnose a brain malformation, tumor, or other structural brain lesion. These tests are more rewarding in younger and older dogs.
There are some general truths about seizure conditions. Each seizure episode often predispose to more episodes, as abnormal brain cells tend to recruit surrounding cells to behave abnormally. Prolonged seizures can be life-threatening. This is because the muscles of breathing can be paralyzed therefore depriving the brain and other vital organs of oxygen. Intracranial causes of seizures can rarely be cured. The aim of treatment with these causes is to decrease the severity and frequency of the seizures. Treatment generally consists of anti-convulsant medications.
To proceed with anti-convulsant medication an evaluation must be made of risks and benefits. Using anti-convulsant medications is usually postponed until the pet has had reoccurring seizures and demonstrates a trend of increased frequency or severity of episodes. Early on, owners are encouraged to keep a journal recording the date, duration, and character of the seizures as well as any observed behavior before and right after episodes occur. It is helpful to diagnose by recording the episodes on video when possible. Animals whose seizures happen every 3-6 months may require no treatment. Some owners become adept at recognizing their pet’s altered behavior preceding a seizure. During any seizure it is important not to put your hand in or near the animal’s mouth.
In some cases, it is recommended to consult with a veterinary neurologist for complete diagnosis, treatment plans, and anti-convulsant therapy. Please consult with Dr. Alexander about possibility of referral to a neurologist.