I usually only now have a yearly blood test which looks at the TSH and was due one now. A month ago my T3 was withdrawn and I was switched to just T4 and told to have my blood tested in a month. After a few days I was poorly and switched back to my usual regime and went for the blood test this week to find written on the form T (not on Thyroxine not on Carbimazole). I am on Thyroxine so what would this tell him. I've never heard of just T before.