Canine Thyroid Imbalance

Dachshunds are among the breeds prone to hypothyroidism.
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Your dog's thyroid glands are located in his throat, one on either side of the trachea. They regulate his metabolism. When they go out of whack, all sorts of problems ensue. Thyroid imbalances consist of too little thyroid hormone produced, a condition called hypothyroidism, or too much, called hyperthyroidism. Fortunately, hypothyroidism usually responds to veterinary treatment. The outcome for hyperthyroidism depends on other factors.


Hypothyroidism is the most common type of hormone imbalance in canines. Symptoms of insufficient amounts of thyroid hormone circulating in your dog's body include hair loss, lethargy, weight gain, frequent skin infections, cold intolerance and scaly skin. If you clip your dog's coat, it might not grow back. Severely affected dogs might experience seizures or eye issues. Your vet performs a physical examination on your dog and tests his blood for thyroid hormone levels.

Affected Breeds

While any dog can develop hypothyroidism, certain breeds are more prone to the disorder. These include the dachshund, poodle, Old English sheepdog, German shepherd, Airedale, cocker spaniel, golden retriever, miniature schnauzer, Labrador retriever, greyhound, Doberman pinscher, Irish setter, Scottish deerhound and boxer. In some of these breeds, hypothyroidism can bring on personality changes, especially aggression. Hypothyroidism generally appears in middle-age or old canines who are spayed or neutered.


Your vet will likely prescribe thyroid pills for you to give to your dog once or twice daily. Since thyroid levels require careful monitoring, you'll make regular vet visits to have your dog's blood tested and his medication dosage adjusted if necessary. Your dog will be on this medication for the rest of his life.


Hyperthyroidism occurs quite in felines but less so in canines. It generally develops because of thyroid cancer. Symptoms include excessive drinking and peeing, weight loss despite voraciousness, breathing difficulties and an overall unkempt appearance. Your vet might prescribe medication to lower thyroid hormone output. Surgical removal of one thyroid gland is an option. Treatment for hyperthyroidism might overlap with that for thyroid cancer. Unfortunately, if the cancer has metastasized, or spread, the prognosis isn't good.