Diet is an often overlooked component of treating dogs with epilepsy. No, I’m afraid I don’t have any insider information on a miracle food that prevents seizures. The ketogenic diets that help many human epileptics don’t seem to be very effective in dogs, and research has not shown a link to any particular ingredient that when removed, leads to a decrease in seizures. That said, keeping a close eye on an epileptic dog’s diet is still vital for several reasons.
Most dogs with moderate to severe epilepsy receive phenobarbital and/or bromide, and changing the diet can alter the activity of these drugs. Research shows that the proportion of protein, fat, carbohydrate, and other nutrients in the diet has an effect on how long phenobarbital remains in the body. Therefore, a change in diet can effectively result in a dog being under or overdosed with phenobarbital even when the amount that is given remains unchanged.
A similar situation exists with bromide and the mineral chloride (a component of table salt and other ingredients). When a dog eats more chloride, bromide is excreted at a faster rate from the body, meaning that higher doses of the drug are required. A study looking at the chloride content of commercial dog foods found levels that varied between 0.33% and 1.32% on a dry matter basis. The amount of chloride in dog food does not need to be reported on the label, so if an owner were to switch diets and inadvertently quadruple the amount of chloride a dog was taking in, breakthrough seizures could result.
Avoiding variability in an epileptic dog’s diet is extremely important, but that does not mean dietary changes are forbidden. If a dog is diagnosed with epilepsy and eating a poor diet, he should immediately be switched to something better. I prefer high quality diets made by large, reputable manufacturers because they are more likely to be able to consistently source their ingredients. Even so, changes to formulations do occur, so owners should watch the label for anything new. Home cooking is also an excellent choice for epileptic dogs when owners have the time and willingness to work with a veterinary nutritionist.
Another instance when changing an epileptic dog’s diet might be a good idea is when symptoms of food allergy are present (usually chronic itching and sometimes GI upset). Food allergies may (and I emphasize the word “may”) play a role in some cases of epilepsy so putting the patient on a hypoallergenic diet and monitoring seizure activity would be worth a try.
When dogs who have been receiving anticonvulsant medications for a long period of time must eat something new, owners should watch very closely for changes in seizure frequency and severity as well as for signs of medication overdose (typically sedation and GI effects). If anything out of the ordinary is noted, a veterinarian can check the dog’s blood levels of phenobarbital, bromide, and/or any other anticonvulsant medications he is taking and compare them to previous results.