Sue -- Cushings and thyroid often (pretty much usually) go hand in hand. The only way to diagnose thyroid issues is with actual thyroid blood tests...so that's how I'd think the 1st vet diagnosed a thyroid problem. I can't imagine the 1st vet giving prescriptions for thyroid meds without a diagnosis.
If that's the case the dog absolutely MUST be on thyroid meds or its life will not only be miserable, but also dangerously unhealthy. If the dog also has Cushings or Atypical Cushings, then they'd also be on a specific drug for that (usually a rather toxic med, in low doses).
If your friend is unsure about the thyroid, a simple thing to do is to run a thyroid panel, and then she'll have a very clear answer.
Btw, it's not surprising or unusual if the 1st vet missed the Cushings for years. It's a *very* tough thing to discern and diagnose. And unfortunately, many generalists don't even think of it when a dog comes in w/ a lot of vague symptoms. There are some cardinal symptoms though, and if those were missed...then the vet really does need a refresher.
Tell your friend that with the Cushings, it can take a very long time (once diagnosed) to actually get the Cushings meds properly titrated...it can easily take up to a year...just fyi. Lotsa patience required
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