What is Hyperthyroidism?
Hyperthyroidism occurs when too much thyroid hormone is produced, increasing your dog’s metabolic rate to dangerous levels. This disease is rare in dogs and much more common in cats, but when it is present in dogs, it is typically serious.
Causes
A type of cancer, thyroid carcinoma, is the primary cause of hyperthyroidism in dogs. Once diagnosed, your vet will discuss the treatment options and prognosis. These options will vary depending on the cancer stage, tumor size, and the extent of nearby tissue involvement.
Symptoms
Weight Loss
Hyper-excitability
Increased Appetite
Increased Thirst
Increased Urination
Enlargement of the Thyroid Gland
Vomiting
Diarrhea
Increased Amount of Stool
Congestive Heart Failure
Tachycardia (fast heart rate)
Heart Murmurs
Cardiomegaly (enlarged heart)
Dyspnea (shortness of breath)
Treatment
There are several treatment options available for thyroid carcinoma including: surgery, chemotherapy, or radiation treatments. Your vet’s recommendation will vary depending on the patient’s condition. In the meantime, there are medications available to counteract the excess hormone levels to keep your pet comfortable.
Prognosis
The long-term prognosis for dogs with hyperthyroidism and thyroid carcinoma is poor to grave. The most accurate prognosis can be given by your vet once examining their condition.
Source:
American Kennel Club: https://www.akc.org/expert-advice/health/thyroid-disease-in-dogs/