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Hyperthyroidism in Dogs FAQ

While relatively rare in dogs, hyperthyroidism is a serious health concern that requires fast treatment in order to achieve the best possible treatment outcomes. Today our Santa Cruz vets answer basic questions about hyperthyroidism in dogs.

What does the thyroid do for dogs?

The thyroid is located in your pup's neck and is responsible for producing a number of important hormones which help to regulate your dog's body temperature and metabolism.

When thyroid hormones are too high or too low they can cause serious health issues for your dog. If your pup's thyroid is producing too much hormone, they will be diagnosed with hyperthyroidism.

What causes hyperthyroidism in dogs?

Hyperthyroidism is becoming increasingly common in cats, however it is still relatively rare in dogs. When this condition is diagnosed in dogs it is a very serious health concern. In most cases hyperthyroidism in dogs is the result of thyroid carcinoma, which is an aggressive and fast growing cancer.

What signs point to hyperthyroidism in dogs

In the early stages of the disease many dogs will show no symptoms at all, or perhaps just a lump on the underside of their neck. When symptoms are evident they can include:
  • Weight loss
  • Gagging
  • Increased urination
  • Vomiting
  • Increased stool
  • Shortness of breath
  • Hyper-excitability
  • Increased thirst
  • Enlargement of thyroid
  • Diarrhea
  • Congestive heart failure
  • Change in bark
  • Difficulties swallowing
  • Increased appetite
  • Rapid heart rate
  • Enlarged heart
  • Facial swelling
  • Heart murmurs

How is hyperthyroidism diagnosed in dogs?

Upon examination, your vet may be able to feel a thyroid mass in your dog's neck, or note an increased heart rate. Diagnostic bloodwork, analyzing thyroid hormone levels will likely be done to help confirm a diagnosis of hyperthyroidism. Following diagnosis further testing may be recommended to help determine the extent of the disease and most appropriate treatment options.

How are dogs with hyperthyroidism treated?

When it comes to hyperthyroidism in dogs, surgery to remove the thyroid tumor typically has the best outcome provided that the mass is freely movable, less than 4cm in size, and has not yet spread to other parts of your pet's body.

Other treatments such as chemotherapy, radiation therapy and/or iodine therapy may also be used, either alone or in combination, depending on the stage of the thyroid cancer, tumor size, and the extent to which nearby tissue is affected.

Left untreated thyroid tumors are likely to grow very quickly and spread to other parts of your pet's body.

What is the prognosis for a dog diagnosed with hyperthyroidism?

The prognosis is good for dog's that are diagnosed and treated early. With appropriate treatment many dogs can go on to enjoy a long survival time, and excellent quality of life.

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.

If your dog is showing symptoms related to hyperthyroidism contact our Bartlett vets right away to book an examination for your pup. At Hillcrest Animal Hospital our compassionate vets offer a range of veterinary services to help your dog feel better.

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Pacific & Santa Cruz Veterinary Specialists is always accepting new patients! Our experienced vets are passionate about restoring good health to Santa Cruz companion animals. We are open 24/7 to provide your pet with care, whenever they need us.

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