REVIEW OF SEIZURES/EPILEPSY IN ANIMALS
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Coauthored with Diana R. Laverdure
Dedicated to the memory of our dear friend and trailblazer, Joanne Carson, PhD, Founder of Canine Epilepsy Guardian Angels
Seizures are the most common neurological disorder in dogs (Wong, 2013). Witnessing a beloved dog in the throes of a seizure is terrifying; the fear that he will injure himself, that he shouldn’t be left alone or that his quality of life will suffer so much that you will be forced to make a dire decision regarding his future are all enough to cause feelings of helplessness and constant stress in even the most resilient dog parent. But the good news is that seizures do not necessarily get worse over time, and there are proactive steps that can help reduce both their intensity and frequency (Canine Epilepsy Guardian Angels, 2011).
Minimizing the total number of seizures and decreasing their frequency is critical, since it’s theorized that every time the brain has a seizure, it “learns” how to have the next seizure. This phenomenon is called “kindling,” and essentially it means that the more seizures a dog has, the more likely he will continue to have them. It is a vicious cycle that becomes harder to break with each episode (Canine Epilepsy Guardian Angels, 2011).
Seizures result from abnormal bursts of electrical activity in the brain. There are three main types:
• Extracranial, which are caused by outside factors that affect the brain, such as a poison or low blood sugar. Diagnosis is made via blood and urine tests.
• Intracranial, or structural, result when there is something wrong inside of the brain, such as a brain tumor. These are more worrisome and are diagnosed via MRI and spinal tap.
• Idiopathic, which are the most common type, result from a functional problem in the brain in which the neurons over-fire, causing the brain to become excessively excitable. Idiopathic seizures typically appear in dogs between one and five years of age and most commonly affect Cocker Spaniels, Labrador Retrievers and German Shepherds, although any breed can suffer from them (Wong, 2013).
Specific causes of seizures include:
• Brain tumors
• Certain medications
• Environmental toxins
• Fever
• Food toxins
• Hypoxia (inadequate levels of oxygen in the blood or tissues)
• Infection
• Inflammation
• Inherited structural problems in the skull or brain (e.g., Syringomyelia, where a cyst forms in the spinal cord, damaging the spinal cord and injuring nerve fibers that carry information from the brain to the extremities. This is especially prevalent in Cavalier King Charles Spaniels.)
• Liver problems
• Low blood sugar
• Meningitis
• Metabolic diseases (e.g., diabetes mellitus, thyroid disease)
• Parasites
• Sinus or ear infections
• Strokes or clots
• Stress
• Systemic diseases (e.g., kidney or liver failure)
• Tick-borne diseases
• Traumatic injuries
• Vaccinosis (adverse effects of vaccines)
• Viruses (e.g., distemper, rabies)
(Canine Epilepsy Guardian Angels, 2011; Wong, 2013)
Be aware of the following signs that indicate the dog is having a seizure:
• Falling over onto side
• “Star gazing” or “fly snapping”
• Convulsions
• Loss of consciousness
• Salivation
• Stiffening and paddling motion of the legs
• Uncontrolled urination and/or defecation
• Vocalization
While one usually cannot stop a seizure once it’s started, steps to help reduce the severity and frequency include the following listed below.
Eliminate Environmental Toxins and Other Exposures
Resistance to all disease involves an optimally functioning immune system, which can be damaged by environmental and food toxins. Many other types of toxins have been linked to neurological issues.
Certain flea and tick treatments are unsuitable for dogs with seizures. The topical spot-on flea and tick control products continue to raise concerns about their safety. In particular, products containing organophosphates and carbamates pose severe health risks and should not be used on pets. Organophosphates are neurotoxins that kill insects by interfering with the transmission of nerve signals in their brains and nervous systems. Like organophosphates, carbamates are toxic to the brain and nervous system. If the product label lists atropine as an antidote to poisoning, the product most likely contains carbamates.
Spot-on flea and tick products containing pyrethroids have gained popularity over the last decade, as they are considered to be less acutely toxic to birds and mammals than organophosphates and carbamates. However, these insecticides carry their own potential toxicity risks. Pyrethrins are botanical insecticides derived from certain species of chrysanthemums. They work by penetrating the nerve system and causing paralysis and eventual death of the target pests and have been linked with dizziness, headache, nausea, muscle twitching, reduced energy, changes in awareness, convulsions, loss of consciousness, hyperexcitability, tremors, profuse salivation and seizures in companion animals. Other flea and tick control products that are contraindicated for dogs prone to seizures are those containing spinosad (Comfortis®, Trifexis®), afoxolaner (NexGard™), or fluralaner (Bravecto™).
Vaccines are linked to seizures. Distemper, parvovirus, rabies and, presumably, other vaccines have been linked with polyneuropathy, a nerve disease that involves inflammation of several nerves. Symptoms of polyneuropathy include muscular atrophy (wasting away of the muscle), the inhibition or interruption of neuronal control of tissue and organ function, muscular excitation (stimulation of muscle fibers), incoordination (poor muscle control or coordination), weakness, and seizures. In addition, MLV (modified live virus) vaccines are associated with the development of temporary seizures in both puppies and adult dogs that belong to susceptible breeds or crossbreeds (Dodds, 2001).
Check Thyroid Function
Low thyroid function, known as hypothyroidism, can precipitate or aggravate existing seizure disorders. While the exact mechanism of how this works is unknown, it may relate to the important role thyroid hormones play in cellular metabolism of the central nervous system. In some cases, simply giving a hypothyroid dog the appropriate levels of thyroid medication reduces the severity and frequency of the seizures, and may even stop them altogether. If a dog has seizures, it’s important that he has a full thyroid antibody test profile run including Total T4, Free T4, Total T3, Free T3, and Canine Thyroglobulin Autoantibody (TgAA). T3 Autoantibody (T3AA) and T4 Autoantibody (T4AA) can also be added. Since many veterinarians do not fully understand how to properly test for canine thyroid dysfunction, the condition often goes undiagnosed or misdiagnosed, and the dog unfortunately suffers unnecessarily. For this reason, it’s critical to carry out the testing at a lab specializing in interpreting thyroid dysfunction in dogs, such as Hemolife’s diagnostics lab. For more information on canine thyroid disorders, the most common endocrine dysfunction in dogs, please refer to our book, The Canine Thyroid Epidemic, DogWise Publishing, 2011.
Avoid Certain Dietary Ingredients
Dogs prone to seizures should not eat the following:
Foods that promote inflammation. Inflammation affects every organ in the body, including the brain, so it probably comes as no surprise that inflammation can cause seizures. Dogs prone to seizures should not consume any potentially inflammatory ingredients, including foods that trigger allergies or intolerances/sensitivities, such as chemical additives, wheat, corn, soy, beef or cow’s milk products—but remember that it can also include any food that causes a problem for an individual dog. For dogs with seizures, we advise testing with NutriScan to identify any problematic food ingredients. In particular, never give products containing gluten to dogs with seizures, since gluten is specifically linked with neurological disorders, including epilepsy, and promotes autoimmune thyroiditis (Kresser, 2010; Hyman, 2013).
Foods that cause fluctuations in blood sugar. Sugars can disrupt the body’s equilibrium or homeostasis, possibly leading to seizures (Wilson, 2013). Avoid giving seizure-prone dogs carbohydrates with a high glycemic index (GI), including honey, sugars, white rice, wheat, corn, white potatoes, carrots, and peas.
Foods containing glutamate and aspartate. Glutamate and aspartate are two excitatory non-essential amino acids (Stafstrom, 2004; Wilson, 2013). Foods high in these amino acids include: grains, especially wheat, barley and oats; all cow’s milk products (opt instead for goat’s milk, which is much lower); beans, especially soy, pinto, lima, black, navy and lentils; nuts, especially peanuts, cashews and pistachios; seeds, including sunflower and pumpkin; any food sweetened with aspartame, such as NutraSweet and Equal; rabbit; turkey; and monosodium glutamate (MSG), a glutamine salt. MSG is used in many prepared foods and can appear on pet food labels under a number of pseudonyms, including “hydrolyzed vegetable protein”, “soy protein extract” and “textured vegetable protein” (Wilson, 2013). These foods should also be avoided in dogs with liver disease.
Rosemary and oregano. Rosemary is commonly added as an antioxidant and anti-inflammatory to commercial pet foods. While likely fine for most dogs, it is a neurotoxin that can promote seizures in vulnerable dogs. Oregano is also a powerful neurotoxin and should not be fed to epileptics.
Vitamin/mineral deficiencies and seizures. Many vitamins and minerals are important for normal functioning of the nervous system. Deficiencies in the minerals calcium, magnesium and sodium, for example, can affect electrical activity of brain cells and result in seizures (Schachter, 2006). Calcium and magnesium, as well as zinc, are also referred to as sedative minerals because they are calming for the nervous system (Wilson, 2013). Antioxidant vitamins (A, C and E) help boost the immune system and fight inflammation. Perhaps the most important vitamins to protect against seizures are the B vitamins.
DNA Methylation: an Explanation for the “Kindling” Effect?
Kindling is a phenomenon whereby the more seizures an individual has, the more he will tend to have. Recently, scientists have uncovered a possible reason for this phenomenon; which, not surprisingly, lies within the purview of epigenetics. Epigenetics affects how DNA methylation impacts upon gene expression; and scientists are now recognizing that DNA methylation also regulates processes that lead to neurologic disorders. A recent “methylation hypothesis” suggests that seizures themselves induce epigenetic modification of chromatin (the combination of DNA and proteins that make up the contents of a cell’s nucleus) in a manner that aggravates an existing epileptic condition (Kobow, 2011). This means that, quite literally, seizures “teach” cells how to have more seizures and that we can and need to interrupt this genomic “lesson” by reducing the frequency of attacks. This hypothesis certainly provides a plausible explanation for the kindling effect, since everything that happens in the body originates at the cellular level.
Since vitamin B-12 and folate promote optimum functioning of the DNA methylation cycle, deficiencies can lead to seizures. Deficiency in biotin, another B-vitamin that modulates chromatin regulation, can also cause epilepsy. In people, a rare inherited form of seizures known as pyridoxine-dependent epilepsy results from mutations in the ALDH7A1 gene, which leads to impairment of normal vitamin B-6 function. Pyridoxine is involved in the breakdown of amino acids and the production neurotransmitters, chemicals that transmit signals in the brain. Pyridoxine-dependent epilepsy does not respond to traditional medical therapy and is treated with high daily doses of pyroxidine (National Library of Medicine, 2013).
Thus, consuming a diet rich in B vitamins may help lower the susceptibility to seizures through their epigenetic ability to regulate gene expression (Foti & Roskams, 2011).
Omega-3 Fatty Acids: Too Important to Ignore
Research on the effects of omega-3 fatty acids and epilepsy are still in the early stages, however, we believe that this important nutrient makes perfect sense to help combat seizures. Omega-3s contain potent anti-inflammatory properties, and inflammatory mediators are increased in epileptic patients. Omega-3s also increase seizure thresholds, promote optimal brain development and modulate neuronal excitability (Stafstrom, 2004; Yuen et al., 2005).
Ketogenic Diet: Proven Effective for People, but not for Dogs
A ketogenic diet contains high amounts of fat, low carbohydrates and moderate protein. Under normal circumstances, glucose broken down from carbohydrates is the primary form of dietary energy. By severely limiting carbohydrates (and thus glucose), the ketogenic diet mimics a constant state of starvation, forcing the body to burn fat for energy. The diet gets its name because the fat is converted to ketones that are utilized as energy in place of carbohydrates. Ketogenic diets are often used in people who do not respond to seizure medications, especially children. While it’s uncertain why they work, about two-thirds of people on a ketogenic diet show significant improvement. But the diet can cause serious health problems, including GI tract upset, hyperlipidemia, renal calculi, stunted growth and pancreatitis (Carr, 2013).
Ketogenic diets have never been proven effective, or safe, in dogs (Thomas, 2011.) In a 2005 study, researchers compared the effects of a ketogenic diet containing 57% crude fat, 5.8% NFE (carbohydrates) and 28% crude protein to a control diet containing 16% crude fat, 25% crude protein and 54% NFE (carbohydrates) in dogs diagnosed with idiopathic seizures. The objective of the study was to determine if the ketogenic diet resulted in a significant reduction in seizure frequency. The dogs were all receiving phenobarbital and/or potassium bromide and had experienced at least three seizures in the three months prior to the study. All of the dogs were fed the control diet for a monitoring period of three to six months while their seizure frequency was established. Dogs that had suffered five or more seizures during that time were randomly divided into two groups; one group continued to receive the control diet, while the other group received the ketogenic diet. The dogs were evaluated at 0, 0.5, three and six months. Of the 12 dogs that completed the trial, there was no difference in seizure frequency between the group fed the ketogenic diet and the control diet (Carr, 2013; Coates, 2013).
The fact that dogs can naturally tolerate longer periods without eating likely accounts for their lack of response to the ketogenic diet. A high fat/low carbohydrate diet apparently just does not create the same biochemical changes in canines as it does in people (Coates, 2013). Moreover, ketogenic diets may create adverse health effects in dogs. Pancreatitis is a serious condition that often results from an excess of dietary fat. Due to a lack of proven efficacy and safety, we do not recommend a ketogenic diet for dogs with seizures.
Could Seizures Originate in the Gut?
The importance of maintaining gut health and the role played by a compromised gastrointestinal (GI) system in leading to a whole host of medical conditions cannot be overstated. Further, imbalances in intestinal microbial flora can also produce seizures. The condition is known as “abdominal epilepsy” and it occurs due to the gut-brain connection. Abdominal epilepsy occurs when an unhealthy microbial environment in the gut creates toxins that cross into the brain. In addition, sections of the intestine known as Peyer’s Patches, where the gut connects with the lymphatic system, are closely associated with nerve bundles and fibers directly connected with the brain, so intestinal irritation may result in seizures via this pathway. Many veterinarians misdiagnose and so do not treat this type of seizure because rather than looking in the gut, they only look at the patient “from the neck up.” If a dog suffers from seizures in combination with ulcerative colitis, manic itching or GI trouble (e.g., constipation and/or diarrhea) he may have abdominal epilepsy.
Gelatin: Friend to the Dog Brain
Gelatin, a potent anti-inflammatory and brain protective food, is an important supplement for dogs with epilepsy (as well as for arthritis and hip dysplasia). The primary amino acid in gelatin is glycine, which is known to protect against seizures and brain damage (Canine Epilepsy Guardian Angels, 2011). Plain, unflavored gelatin can be added to the diet in many ways, such as sprinkling it on the dog’s food or making treats out of it. However, never use Jell-O or other gelatins intended for dessert, as they contain sweeteners (either sugar or artificial) that can potentially worsen the seizure condition (remember that the artificial sweetener, Xylitol, is toxic to dogs).
Suggested Dose: (give twice a day, added to food)
• 10 to 25 lbs: 1 tsp (teaspoons)
• 25 to 50 lbs: 3 tsp
• 50 to 75 lbs: 6 tsp
• 75 to 100 or more: 3 tablespoons
Joanne’s Gelatin Dog Treats
This simple recipe for gelatin treats is provided courtesy of the late Joanne Carson, PhD, Founder of The Epi Guardian Angels. They are like Gummy Bears for dogs!
Ingredients:
• 1 cup of unflavored gelatin
• 1 cup of cold, flavored liquid (such as broth)
• 1 cup of boiling liquid (either water or broth)
Put 1 cup of gelatin in a 1-quart bowl. Add 1 cup of the cold liquid and let stand one minute to soften. Pour 1 cup of boiling liquid (water or broth) over the softened gelatin, and stir until the gelatin completely dissolves (about five minutes or less). For chewier treats, add more gelatin. Pour the mixture into a 9 x 12 inch pan and let harden. Cut into 1 by 3 inch strips or an appropriate size for the dog.
It’s estimated that 20% of dogs on phenobarbitol anti-seizure medication develop liver enzyme induction (Canine Epilepsy Guardian Angels, 2011). Liver cleansing herbs such as milk thistle and/or SAMe can be helpful.
Case Study Success!
Coal and corn do not mix.
Coal, a two-year-old female black Labrador Retriever, experienced seizures every other month. Hoping to avoid treating her with anti-seizure medication, Coal’s guardians weaned her over to a prepared raw diet with lamb as the meat source. After discussing the options, an anti-inflammatory diet was chosen as the primary treatment. Coal was also treated with Western herbs (lime blossom, valerian and chamomile) as well as coconut oil. The seizures stopped. Six months later, however, Coal experienced another seizure after finding some taco shells in the garbage (made from corn). She had yet another seizure one month later, which her guardians attributed to eating leftover popcorn from a slumber party. Three months later, Coal had another seizure and her guardians remembered that she had licked several plates clean after a dinner that included corn-battered meat and frozen corn. Over the next four years, Coal had only three seizures — all of which were connected to an episode of eating corn! Thankfully, she never required anti-seizure medication.
* Adapted from: Dodds, WJ, Laverdure, D R. (2015) Canine Nutrigenomics: The New Science of Feeding Your Dog for Optimum Health, Chapter 11; DogWise Publishing, Wenatchee, WA.
W. Jean Dodds, DVM
Hemopet / NutriScan
11561 Salinaz Avenue
Garden Grove, CA 92843
