Canine Hypothyroidism

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Brooker Ridge Animal Hospital

Veterinary Hospital in Newmarket


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Canine Hypothyroidism

Brooker Ridge Animal Hospital
Thyroid Problem in Dog. Is My Dog Fat?.

Hypothyroidism in Dogs
The thyroid gland is a vital hormone gland located in the neck produce hormones that plays a major role in the metabolism, growth and body development.

Dogs with thyroid Problem usually have a low production of thyroid hormones. Overproduction of thyroid hormones in the dog is rare and usually associated with cancer.

Fortunately, Thyroid cancer is uncommon in dogs. Hypothyroidism is usually caused by inflammation or shrinkage of the thyroid glands. It occurs more commonly in medium to large breed dogs and usually in middle aged dogs. Breeds commonly affected include:
• Golden Retriever.
• Doberman Pinscher.
• Irish Setter.
• Miniature Schnauzer.
• Dachshund.
• Cocker Spaniel.
• Airedale Terrier.

Clinical signs
Many of the clinical signs such as mental dullness, lethargy, exercise intolerance, and weight gain despite normal appetite are directly related to slowing of cellular metabolism. The most common signs of low thyroid function in dogs include hair loss, dull hair coat, excess shedding or scaling, thickening of the skin, weight gain, reduced activity, and reproductive disturbances in intact dogs and reduced ability to tolerate the cold.
Hair loss is not associated with itchiness, it is usually bilaterally symmetric that may involve the ventral and lateral trunk, dorsum of the tail, the caudal surfaces of the thighs, ventral neck, and the dorsum of the nose. The alterations in the skin and coat are sometimes associated with hyperpigmentation.

Occasionally, hypothyroid dogs may also develop skin infections (pyoderma) which may be itchy and result in sores on the body. The accumulation of mucopolysaccharides can cause the muscles of the face to droop giving the dog a “tragic” facial expression.

Neurologic disorders are less commonly seen in dogs with hypothyroidism, including dilation of the esophagus (megaesophagus) causing regurgitation, laryngeal paralysis, facial nerve paralysis, and vestibular disease, have been related to hypothyroidism.

Canine Hypothyroidism Diagnosis
In routine wellness blood tests, your vet may notice a mild anemia and increased levels of cholesterol in dogs with hypothyroidism.
Hypothyroidism is probably one of the most overdiagnosed diseases in dogs. A variety of nonthyroidal illness can lead to low serum thyroid hormone measurements in euthyroid dogs or cats. If you notice one or more of these clinical signs, talk to our vet in Newmarket. Our veterinarian may need to run some diagnostic tests such as measurement of the serum concentrations of total T4, free T4, and/or TSH for diagnosis of canine hypothyroidism.

How is Canine Hypothyroidism Treated?
Treatment of hypothyroidism is by giving oral replacement hormone for the rest of the dog’s life. Initially thyroid hormone is usually given twice daily. Once the hair coat begins to improve, some dogs can be maintained on once daily medication. Almost all hypothyroid dogs receive T4 (levothyroxine or L-thyroxine).
T4 is converted to T3 by the body. A few dogs are unable to make this conversion and require T3 medication.
It usually takes 4 to 6 weeks for hair to regrow.
If you have concerns about your dog's weight or suspect your dog is hypothyroid, take your dog to our veterinarian in Newmarket at Brooker ridge Animal Hospital. We treat hypothyroidism and other related health issues that could cause weight gain. Call 905-898-1010 to schedule your pet's appointment.


Brooker Ridge Animal Hospital - 905-898-1010

107-525 Brooker Ridge, Newmarket, ON L3X 2M2

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