Six months ago my blood tests showed TSH 5.18 (range 0.27- 4.2) FT4 13.5 (range 12.0-22.0) no T3 given. Based on this my doctor raised my levythyroxine from 650gram per week (100gram 6 days and 50 gram 1 day) to 700grams per week, 100 per day. Now six months later my bloods show TSH .31 (range 0.27- 4.2) FT4 20.3 (range 12.0-22.0) and T3 1.11 (range 1.3-3.1). How soon should you be re-tested after a change in dosage? Six months seems a long time to wait. My dosage has been changed back to 650gram per week with no mention of a test to check levels in the future.