However, for unknown reasons, some people convert slowly, and even though their FT4 levels can be very good or even a little on the high side, their FT3 remains low. For those people, adding a little medication
with T3 in it can make a world of difference. T3 is marketed in the U.S. as Cytomel, but there are also generics. Another option is desiccated porcine thyroid which contains both T3 and T4 (e.g. Armour thyroid).
My experience with BPPV was rotational...