Hypothyroidism is a disease of thyroid deficiency. In this condition, thyroid harmones such as T3 (liothyronine) and T4 (levothyroxine), which are essential for regulating body metabolism, are produced and released in low quantity. It is common in medium to large-sized dogs, with some being more predisposed than others. Breeds that are more prone to this disorder are Doberman pinschers, Irish setters, golden retrievers, great Danes, old English sheepdogs, dachshunds, miniature schnauzers, boxers, poodles, and cocker spaniels.
It is also more commonly diagnosed in middle-aged dogs between the ages of 4-10 years. Neutered male dogs and spayed females are found to be at higher risk than intact dogs.
Common symptoms include
Lethargy
Generalized weakness
Inactivity
Mental dullness
Unexplained weight gain
Hair loss (alopecia)
Excessive hair shedding
Poor hair growth
Dry or lusterless haircoat
Excessive scaling
Recurring skin infections
Intolerance to cold
Tilting of head to one side (uncommon)
Seizures (uncommon)
Infertility (uncommon)
