Dietary Supplement Use in Canine Epilepsy

Dietary supplements and dietary changes are often employed by owners of epileptic dogs, with the intent to reduce seizure frequency or severity, or to prevent or reduce side effects of anti-epileptic drugs (AEDs). In a recently published study, clinicians evaluated the frequency with which owners administered such supplements, which supplements were commonly given, and the owners’ rationale for or against using those supplements. The authors also present a review of current evidence for potential benefit and potential drug interactions for the most common supplements reported.

Study Design

Data were collected through a prospective survey of owners of epileptic dogs, administered online from April to June 2017. To be included in the analyses, dogs must have met the criteria for tier 1 evidence for diagnosis of idiopathic epilepsy based on the International Veterinary Epilepsy Task Force. Once surveys were complete, owners were categorized as having recently used supplements, previously used supplements, or never used supplements as part of the management plan for their pet’s idiopathic epilepsy. For those who used dietary supplements, the questionnaire included the type of supplement administered, how and why the supplement was chosen, the reason for stopping the supplement, and any perceived side effects.

RESULTS:

• Idiopathic Epilepsy and Cognitive Dysfunction in Dogs
• What are the 3 Phases of a Seizure?

Results and Discussion

Of the 547 responses, 297 met the inclusion criteria and were used in the analyses. Respondents were from the United Kingdom, United States, Canada, Germany, and Australia. Most of the dogs included in the study had generalized seizures (71%); 261 (87.8%) received concurrent AEDs. The most frequently administered AED was phenobarbital (n = 207), either alone (n = 61) or in combination with other AEDs (n = 146). Dogs receiving dietary supplements were significantly more likely to have been prescribed multiple AEDs, either in the past or currently (P = .012); however, the number of seizures was not associated with the use of dietary supplements (P = 0.064). Cluster seizures were also not associated with the use of dietary supplements (P = 0.714), but dogs that had experienced a status epilepticus event were more likely to have received dietary supplements (P = 0.004).

Two-thirds of respondents (67.7%) had changed their dog’s diet since they received a diagnosis of idiopathic epilepsy. The frequency of feeding of various diets was dry food (60.6%), dry food combined with wet food (25.6%), raw food (21.9%), and home-cooked food (17.8%). When asked where they sought advice for dietary choices, only 27.6% of respondents said they asked their veterinarian. The most commonly administered dietary supplements were coconut oil (n = 112, 77.3%), fish oils (n = 105, 77.3%), milk thistle (n = 67, 42.7%), and cannabis oil (n = 66, 42%). The most common sources of advice for selection of dietary supplements were online support groups (38.2%), other online information (20.6%), and their veterinarian (17.5%).

Owners cited the most common reasons for administering dietary supplements as reduction of seizure frequency (88.2%), protection from AED side effects (62.5%), reduction of seizure severity (61.8%), improved postictal recovery (42.6%), reduction of AED side effects (41.2%), or reduction of comorbidities (30.1%). Of respondents who gave dietary supplements, 21 had stopped administering them for the following reasons: no recognizable benefit (33.3%), concern regarding potential adverse effects (9.5%), or refusal of the dog to take the supplement (9.5%). Forty-seven percent of respondents did not currently, nor had they previously, given dietary supplements. The majority of owners (92.5%) who had stopped or not previously administered dietary supplements would consider doing so when more scientific evidence was available.

Adverse effects of dietary supplements, as reported by owners, included sedation (n = 29), increase water consumption (n = 24), and weight gain (n = 22).

Clinical Impact

Dietary supplements and nutritional changes are frequently used by owners of dogs with idiopathic epilepsy, most commonly without veterinary supervision. Although adverse events are infrequently reported by owners, there is evidence of interactions with commonly used AEDs, including lowering plasma levels of drugs (eg, with high chloride or sodium intake increasing excretion and lowering plasma levels of bromide, and lower protein intake decreasing plasma levels of phenobarbital). Further, it would be prudent to monitor triglyceride levels or pancreas-specific lipase in patients administered additional oils as dietary supplements. Given that dietary supplements are commonly administered by owners, it is important to the patient’s well-being for veterinarians to engage owners in conversations, ensure dietary consistency, and monitor for side effects and potential AED interactions.

Dr. Packer is an associate professor of neurology/neurosurgery at Colorado State University College of Veterinary Medicine and Biomedical Sciences in Fort Collins, and is board certified in neurology by the American College of Veterinary Internal Medicine. She is active in clinical and didactic training of veterinary students and residents and has developed a comparative neuro-oncology research program at Colorado State University.