Potassium bromide is one drug that is commonly prescribed for managing seizures in dogs with epilepsy. Advantages of this drug include its ease of administration - it's available in liquid form or as a chewable tablet and it can be given just once daily (though it may be divided into twice daily dosing to minimize gastrointestinal upset).
One other benefit of this drug is that it is excreted from the body via the kidneys and is not metabolized by the liver. As such, this drug is a good consideration for animals with liver function concerns. Of note, there are important dietary considerations for pets taking bromide. Because this drug is excreted by the kidneys, it does compete with chloride for processing (by the kidney) and absorption by the renal tubular system. Therefore, changes in chloride levels (in the bloodstream) are going to affect bromide levels. This is important to understand because changes or fluctuations in bromide levels can impact its effectiveness in controlling seizures.
Salt in the dog's diet is the most common source of chloride in the body. When prescribing bromide and working to determine the optimal dosage for the individual pet, it's very important to keep the dog on a consistent diet. Whether the dog is on a low salt or high salt diet, abrupt changes in the amount of salt that the dog consumes can lead to problems. If a dog is on a low salt diet then bromide will be preferentially absorbed and result in higher blood concentrations of the drug. Conversely, if a dog is on a diet that is higher in salt, chloride will be preferentially absorbed and bromide excreted in higher proportions resulting in lower blood concentrations of the drug. Therefore, if a well-controlled epileptic dog (on bromide) were to experience an abrupt change in their diet or consume a food that is high in salt (e.g. pizza or other table scraps) it could cause that dog to develop breakthrough seizures.
In her discussion of the medical management of canine epilepsy, Dr. Karen Muñana - a veterinary neurologist at North Carolina State University - also mentioned the potential danger that a visit to the beach can present for dogs taking bromide. “Here in North Carolina we have a lot of families that come with their dogs to vacation and spend time at our beaches. Over the years we’ve seen some dogs that were well-managed epileptics suddenly develop seizures while on vacation. These dogs had gone swimming in the ocean, ingested a lot of salt water and, in doing so, they essentially flushed the bromide out of their system resulting in seizures while on vacation. So, in addition to making sure that they stay on a consistent diet, we also recommend that dogs taking bromide for seizure control avoid ocean water.”
Dr. Holger Volk, a veterinary neurology expert, explains further:
Learn more about the role of nutrition in managing epilepsy or view the full Canine Epilepsy Summit on demand.
