Epilepsy is a common problem in dogs that usually occurs for the first time before the age of 5 years. Epileptic fits are very alarming to watch but are rarely dangerous. Pet animals do not “swallow their tongue” and will often recover within a minute or two of starting a fit. However, they may appear a little dazed or confused for some hours afterwards. In animals above 5 years of age the onset of seizure activity is unlikely to be associated with epilepsy and these animals require thorough investigation including MRI scans.

If an epileptic fit occurs it is important that we do a routine blood test to rule out other causes of seizures. For example, problems with low blood glucose or low blood calcium can cause fits indistinguishable from true (idiopathic) epilepsy. A routine blood screening test costs about £40.

The “Kindling” Effect – Fuel on the Fire

After a single epileptic fit we recommend that no treatment is undertaken – some dogs may only have a single epileptic fit in their life. However, if 2 or more fits occur we would usually recommend that treatment be started. This is because of a problem known as “kindling” – each fit a dog has makes it more likely that they will have further fits in the future. Thus each fit adds kindling to the fire of epilepsy. In order to manage epilepsy well, it is important to prevent fits as completely as possible. If a dog’s fits are not well controlled it is likely that the fits will start to cluster one after another. In extreme cases, the animal will enter a fit that will continue indefinitely – status epilepticus.

Although it is usually impossible to control fits completely with medication, we are often able to reduce their incidence to such a low level that no progression of the epilepsy occurs. Well-controlled dogs may only have a mild fit every year or so.

Medication

The drug we recommend in the treatment of epilepsy is phenobarbitone, sold under the trade-name “Epiphen”. Phenobarbitone is a very long-acting barbiturate anaesthetic that is broken down by the liver in the same way as alcohol. Just like alcohol, if taken to excess, it can cause liver damage and severe health problems.

Fortunately, at the dose rates used for the treatment of epilepsy, severe side effects are rare and some dogs suffer no side effects at all, even after many years on medication. Epiphen usually causes some drowsiness when first taken, and your dog may be a bit wobbly on its feet for the first few days. Thereafter, we would expect to see no problems with Epiphen administration. Once treatment begins, it continues for life. It is usually impossible for the dog to stop taking medication without fits occurring very quickly after withdrawal.

THERAPEUTIC MONITORING

In order to make sure that we are not overdosing this powerful drug, we monitor blood levels of phenobarbitone two weeks after first administration and two weeks after any change in dosage. We also do further blood tests every six months to ensure that levels are still within safe limits. If proper therapeutic monitoring is performed, it is very unlikely that your pet will suffer any serious harm as a result of Epiphen administration.

When we purchase Epiphen, we are supplied with a limited number of vouchers that entitle us to free blood tests. We make these vouchers are available on a first come, first served basis to our clients. The blood test for phenobarbitone normally costs in excess of £30. Unfortunately, we are not supplied with enough free vouchers to offer free blood tests on all occasions.

Proper therapeutic monitoring is vital for the safe use of Epiphen. We will not supply prescriptions for this drug unless the animal has had a blood test in the previous 6 months.

COMBINATION THERAPY

Although some pets will have their seizures well controlled with Epiphen alone, this is not the case with all dogs. In cases where pets continue to have frequent seizures despite being dosed correctly with Epiphen, we recommend the concurrent use of Potassium Bromide. This is a simple salt that has some sedative properties and which works very well to prevent fits when used in conjunction with Epiphen. This product is relatively cheap, although we sometimes have difficulty in sourcing a supply since it is not available as a licensed veterinary medicine. This may cause the price of the product to fluctuate between batches. Potassium Bromide should be kept in the fridge and administered in the food. Side-effects are very rare and therapeutic monitoring of blood levels is not generally required with this drug. Therapeutic monitoring can be used if problems occur, however. Unfortunately, Potassium Bromide does not work very well as a sole treatment for seizures.