A.I have been using phos serine for many years since it first hit the market. In those days, I was working closely with the company that did the original work documenting its beneficial effects in humans, especially helping to support proper brain function.
It was then that I learned about a study done on conditioned athletes where phos serine was shown to suppress cortisol output by the adrenal glands without any noticeable side effects. From that point on, I have been using it in Cushing’s patients and have not noticed any side effects.
For a dog the probable weight of your terrier, 100 mg is what we would typically recommend – and many of my clients, over the years, have doubled or tripled our recommendations without any observable side effects. One other supplement you could consider looking into would be Humanofort by Dogtor Rx.