yes, found out about 4 years ago (41 now). i’m on 150mcg per day too, up from 125 from just after diagnosis. not sure if there is a limit, have you asked your doc?
as an added bonus i found out i’m type 1 diabetic last year, so much fun 🙂
after a quick google i found this:
An inadequate response to oral daily doses of 300 mcg/day or greater is rare and may indicate poor compliance, malabsorption, and/or drug interactions
from here:
linky