Hyperthyroidism In Dogs

Idiopathic Epilepsy: Primary Cause of Seizures in Dogs

Seizures of unknown cause affect roughly 5% of all dogs. Of those dogs, over half will eventually be diagnosed with canine idiopathic epilepsy. According to Dr. Ned Patterson of the University of Minnesota , 50–60% of dogs who experience their first seizure between the ages of one and five have no identifiable cause for their condition, which is then considered idiopathic epilepsy. But the prevalence of this seizure disorder in purebred dogs has led researchers to focus on a possible genetic link. And progress is being made in developing tests to identify responsible genes.

In order to fully understand the complexity of diagnosing idiopathic epilepsy in dogs, it is important to have a clear definition of the disorder.  Idiopathic means occurring without known cause and epilepsy is defined as a neurological disorder characterized by unprovoked, recurring seizures that disrupt the nervous system. The age of onset is also important to consider.  Canine idiopathic epilepsy is generally first evidenced between one and five years of age. Dogs may develop seizure disorders later in life, but these are more likely to be linked to age related changes.

There are many things which can trigger seizures: exposure to chemical or plant toxins, viral diseases such as canine distemper, hypoglycemia, hypocalcemia, hypo– and hyperthyroidism and heart disease, for example, can each cause increased neuronal excitability in the brain. Head trauma can result in brain injury, hydrocephalus (a structural abnormality of the brain), tumors (both cancerous and benign), and liver or kidney dysfunction can cause seizures. The diagnosis of idiopathic epilepsy is based on ruling out all possible causes for a dog to be experiencing seizures. So if any of these conditions are present, the epilepsy is considered secondary, rather than primary, as there is an underlying cause.  And because there is a known cause it cannot be considered idiopathic.

Increasingly, the role of genetics in idiopathic epilepsy is being explored. Given the numbers of purebred dogs developing primary epilepsy and the apparent familial links in many of those cases, this avenue of research makes sense. And it is beginning to pan out. The Canine Epilepsy Project is making progress in identifying genetic basis for seizure disorders in dogs. This collaborative effort by the University of Missouri, the University of Minnesota and the Animal Health Trust in the UK, to find the genes responsible will eventually aid dog breeders in their efforts to reduce the prevalence of the disorder in their chosen breeds.

Canine Hyperthyroidism and Thyroid Cancer: Symptoms and Treatment |

Canine Hyperthyroidism and Thyroid Cancer:  Symptoms and Treatment

Hyperthyroidism in dogs is very serious.  Learn the symptoms so you can get proper treatment for dog’s Hyperthyroidism. 

Keywords: canine hyperthyroidism, hyperthyroidism in dogs, dog hyperthyroidism

Canine hyperthyroidism is a rare condition wherein the thyroid glands produce too much thyroid hormone.  Hyperthyroidism is a disease common to humans and cats and is easily treatable, but for dogs hyperthyroidism can be fatal.  That’s because hyperthyroidism in dogs is often a sign of thyroid cancer.  Left untreated, canine hyperthyroidism can be life-threatening for your pet.

Dog hyperthyroidism manifests several warning signs.  The most common symptoms of canine hyperthyroidism are weight loss with increased appetite and excessive thirst.  That’s because the increase in thyroid hormone levels increases your dog’s metabolic rate to the point that your dog is consuming more energy than it can eat.  Sometimes, your dog would be so hungry and eat so much to the point that it would vomit while eating.  Your pet may also experience diarrhea because their body’s digestive system is working too fast.

Another noticeable symptom of hyperthyroidism in dogs is nervousness and hyperactivity.  If your dog is always jittery and can’t seem to calm down, it may be a sign of an overactive thyroid.  This type of restlessness is very uncomfortable for dogs because along with this symptom they’re also experiencing increased heart rate and shortness of breath.  Dogs with hyperthyroidism also experience changes in their coat which could become dull, dry and unkempt as the disease progresses.

If you notice these symptoms in your dog, you should consult a veterinarian in order to confirm the diagnosis of hyperthyroidism.  The first thing your veterinarian would do is to perform a thorough physical exam in order to check if your pet is suffering from any other sign or symptoms that would help point to the right diagnosis.  The next step in the diagnosis would be a blood test to measure the thyroid hormone levels in the body.   This test would confirm the diagnosis of hyperthyroidism.  The last test would be an ultrasound or X-ray of the thyroid to see how big the thyroid tumor is and to see any other abnormalities that may be affecting thyroid function.

When caught early, canine hyperthyroidism is treatable without any major complications.  Hyperthyroidism in dogs can be treated in three ways: medication with antithyroid hormone, surgical removal of the thyroid or thyroidectomy, and radioactive iodine therapy.  The type of treatment would depend on the severity and symptoms of canine hyperthyroidism.  For mild to moderate symptoms of the disease, antithyroid medication can provide immediate and long term relief.  For severe cases where the symptoms are severe and the thyroid carcinoma presents a serious threat, surgery and radioactive iodine treatment.  Thyroidectomy is a procedure that removes the entire thyroid gland or just the diseased portions of it. In radioactive iodine therapy, radioactive iodine is injected into the thyroid, gradually killing the thyroid and cancer cells in it.  Both thyroidectomy and radioactive iodine therapy provide permanent solutions to canine hyperthyroidism and thyroid carcinoma in dogs.

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