This condition is thankfully very rare in dogs
Hyperthyroidism is usually caused by an excessive production of thyroxine brought on by aggressive thyroid cancer.
Another source of raised thyroid hormones is from hypothyroid medication, which usually includes a synthetic form of thyroxine. An over-correction of low thyroxine levels can sometimes result in hyperthyroidism.
Raw food diets that include an excessive amount of thyroid hormones can also cause the condition. These diets often include gullets, head meat, and animal necks, which contain higher levels of thyroid hormones.Coat may become patchy with increased shedding.
Signs & Symptoms of Hyperthyroidism
Coat may become patchy with increased shedding.
Excessive Weight Loss (despite increased appetite)
Increased thirst (Polydipsia) & urination (Polyuria)
Lump in the neck – the enlarged Thyroid gland
Difficulty in breathing (Dyspnea)
Intolerance of the cold.