Tip of the Month

8/15/2011 Hypothyroidism in Dogs

Hypothyroidism is one of the most common hormone deficiencies in dogs, and yet one of the most overlooked. Simply put, when dogs suffer from Hypothyroidism their thyroid gland isn’t producing enough of the thyroid hormone. The causes of this condition can vary. The onset of Hypothyroidism may be from a naturally slowing down gland due to the dog’s age, a congenital problem or in some cases, a tumor on the thyroid gland.

The thyroid gland is located on each side of the trachea (or windpipe). The thyroid gland’s major function is to control the body’s metabolism by circulating hormones in a regulated fashion. It secretes two hormones which are T3 (triiodothyronine), and T4 (thyroxine). T3 is considered the “active” form of the hormone while T4 is what circulates through the blood stream, but is not considered to be active.

Hypothyroidism is most common in medium to larger breed dogs such as the Doberman Pinscher and Golden Retriever, with the age of onset between 4 to 10 years. It seems to be rare in small or toy breeds, although some small breeds such as the Miniature Schnauzer and Dachshund are predisposed to this condition.

Since this condition affects the metabolism, warning signs that owners can look for usually are weight gain and skin conditions. The Veterinary Information Network has noted that 88 of cases had some sort of skin issue and 40 had hair loss. Classically, the hair loss manifests around the tail, giving a “rat tail” appearance. The percentage of overweight animals is about 49 and 48 of owners found that their dogs had become very lazy, or listless. If you suspect your dog may have this issue, it’s very important to make an appointment with your veterinarian or veterinary assistant for testing.

Testing for hypothyroidism is as simple as drawing a bit of blood and sending a blood panel to the laboratory. There are several types of thyroid testing and depending on your dog’s condition; your vet assistant may recommend more than one test.

If it turns out your dog does have hypothyroidism, it can commonly be treated by giving a thyroid supplement orally, usually twice a day. This treatment will be a necessity for the dog for the remainder of the animal’s life. Upon initial treatment, your veterinary assistant will make a follow up appointment with you to have your dog’s thyroid level checked again, to ensure that the thyroid levels are within the normal range. If the level is too high, that may lead to further complications involving the heart or kidneys. If the levels are too low, then the medication will not be working as well as it is intended to do. It is imperative that your dog has the levels rechecked upon initial medicating or if there is a change in dose. If everything has been stabilized with your canine’s medication, you should still have your dog’s levels checked annually. Many times, your vet assistant will request that you bring your dog into the clinic at a specific time, a number of hours after you have administered the medication, for “post-pill” testing. Remember, it may a bit frustrating to tailor the dose or frequency of the medication in the beginning, but once your veterinarian has it perfect, it is smooth sailing for a happy and healthy pet!

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