Another common Westie health condition is hyperthyroidism, a condition in which the thyroid gland produces too much thyroid hormone. Hyperthyroidism can cause a variety of symptoms, including weight loss, increased thirst and urination, and increased appetite. Treatment for hyperthyroidism typically involves medication or surgery.
The average life expectancy of a West Highland white terrier is 12 to 15 years. However, with joint disease, that can be reduced. The severity of the joint disease will affect how much it affects the dog's life expectancy. If a dog has mild joint disease, it may only lose a few years off its life expectancy. However, if a dog has severe joint disease, it may only live to 5 or 6 years old.