Little Bit's liver tests were normal. We checked her thyroid hormone and it was very low. But low thyroid hormone does not mean the dog has hypothyroidism. Thyroid hormone increases and decreases unpredictably through the day so the test level may depend on when the sample was drawn. And furthermore, many other diseases can cause a dog to have a low thyroid hormone level.
Hypothyroidism is an over-diagnosed disease.
It is treated with daily thyroid pills for the rest of the dog's life. Steroids, and perhaps thyroid pills, may make a dog feel better and increase his appetite, whether they are really curing anything or not. A dog with a normal thyroid who doesn't feel good may have a low thyroid test and feel better when given thyroid pills. And then the owner may needlessly buy thyroid pills for the rest of the dog's life. If a dog has hypothyroidism it should be treated.