Veterinary care should include diagnostic tests and subsequent treatment recommendations.Diagnosis In-depth
Your veterinarian will take a detailed history regarding the seizure episodes including any information about the seizure, the breeding or litter history, toxin exposure and their previous health record.
Your veterinarian will perform a complete physical and neurological examination that may include an examination of your pet's retinas.
By definition, idiopathic epilepsy is a seizure disorder with no known cause, although it is important for your veterinarian to determine your pet's general health and make sure there is no underlying disease that may be causing the seizures. Recommended blood tests may include: A complete blood count (CBC or hemogram) to check blood counts
Serum biochemistry tests to evaluate blood glucose, electrolyte and protein concentrations
Bile acid determinations to evaluate liver function
A feline infectious disease panel which includes tests for feline leukemia, feline immunodeficiency virus, feline infectious peritonitis, toxoplasmosis and cryptococcosis
Urinalysis to assess kidney function
Fecal examination to check for parasites
Based upon the presentation, age, breed, seizure episode and results of the above tests a diagnosis of idiopathic epilepsy may be made and treatment may be recommended.
The most overlooked aspect of treatment is keeping a seizure log in which you write down exactly when (time and day) your cat has a seizure, including the total length of the seizure and any predisposing activities that you remember. Note what your cat does during the seizure. If you suspect your cat had a seizure but you did not witness it, list it as a question mark in your seizure log.
Treatment is indicated for idiopathic epileptics depending on the severity and time between seizures. Generally, medical treatment is generally advised for animals who have one or more seizures every six weeks. Cats who have cluster seizures or go into status epilepticus (more than one seizure in a 24-hour period) may be treated even though the time between seizures is greater than six weeks.
If you and your veterinarian decide to treat your cat with an anticonvulsant, you must make a commitment to giving the medications exactly as prescribed with absolutely no changes in the dose or drug without veterinary consultation. Haphazard drug administration or abrupt changes in medication may be worse than no treatment at all and may cause status epilepticus.
The goal of treatment is to reduce the severity and frequency of the seizures while avoiding unacceptable side-effects. It is rare to eliminate completely all seizures in cats with idiopathic epilepsy.
Phenobarbital is usually the drug of first choice for idiopathic epilepsy. It is usually effective in more than 80 percent of the cases when administered at the correct dose and frequency. It is given two to three times a day. During the initial treatment period of 10 to 14 days, side effects are usually seen with this drug consisting of excessive drinking, urinating and eating. Some cats may act very lethargic as well. These side-effects are temporary and diminish two weeks after initiating treatment.
Phenobarbital comes in 15, 30, 60 and 100 mg tablets. Phenobarbital tablets are often referred to according to grains (gr.). For reference 1 grain equals 60 mg. There is also a syrup or elixir available.
Blood phenobarbital concentrations should be measured two weeks after any change in dose or if there is a change in seizures frequency or severity. Concentrations are determined by drawing blood. The level of drug needed to control seizures varies between individual cats but generally should be above 25 ug/dl before treatment is considered failed.
Cats can have liver problems with chronic, high-dose phenobarbital treatment. Regular annual or semi-annual blood tests may be recommended to evaluate your cat's liver function.
The other common anti-convulsant used in cats is oral diazepam or valium given three times a day. Oral diazepam has been linked to a very rare but fatal idiosyncratic hepatic failure. Most veterinarians will avoid this drug in cats if possible. If your cat is on this drug with no problems, it is not necessary to change the medication unless your cat has liver problems like anorexia, vomiting or abdominal pain.
Bromide is the active ingredient in potassium bromide and sodium bromide and is another anticonvulsant that can be used in addition to phenobarbital or as an initial drug. Many cats that do not initially respond to phenobarbital alone will have a dramatic decrease in seizure frequency and severity with the addition of bromide.
Bromide is the drug of choice for animals with liver disease. Bromide is always given on a full stomach. Giving bromide on an empty stomach can cause vomiting. Bromide is not approved for use in cats, nor is it commercially available at this time. Bromide can be given as a capsule or dissolved in water or as syrup.
Bromide has an extremely long half-life which means it can be given once a day. It also takes 6 to 8 weeks to reach therapeutic levels in the blood unless your veterinarian recommends giving a loading dose. Side-effects from the bromide include increased eating, drinking, urinating and incoordination. These side-effects are usually temporary but if they are problematic, a dose reduction in either one of the drugs may be recommended.
Diazepam (Valium) is used for the treatment of status epilepticus. Your veterinarian usually gives it in emergency situations by the intravenous (IV) route. Your veterinarian may recommend diazepam by rectal or nasal administration if your cat has severe seizures. This is not common situation and requires special training.
Alternative therapies range from acupuncture to herbs and vitamin therapies as well as dietary recommendations. Work with your veterinarian in selecting the right treatment for your cat's seizures.
Other drugs such as primadone, phenytoin, gabapentin, zonisamide, levitiracetam, carbamzaine and valproic acid are used in certain specific situation as tertiary drugs.