Abby
Yes, 1.6 is low I think for a sheltie. Harper Lee's was low like that and we brought her up to a high 2. It does take a while to stabilize the thyroid meds though. We are still a work in progress, you also have to be aware that if they lose or gain weight that thyroid adjustments may be necessary. With soloxine her test came back so high one time, we cut her dose in half and now she is stable but every 6 mos. we run it to be sure.
After thyroid meds, her scratching was better but still to this day is not at the 100 per cent that I would hope for her.
We did numerable food switches, now she eats sweet pot, vegetables, and chicken or fish.
Interestingly sometimes when she goes to scratch, and I divert her attention to something else she does not scratch. Some of her behavior might be a little obsessive, it is an ongoing puzzle, but one we are willing to keep trying to solve.
Recently we got her Maleseb, an anti bacterial shampoo that helps with yeast infections of the skin, it was recommended on this site and she is doing much better. At least she is not ripping out her hair like she was last year.
Hope this helps Abby's Dad,
They are worth it all,
Kate