An increase in Levothyroxine won't increase your TSH. Levothyroxine directly affects T4 since that's what it's replacing. An increase in T4 would actually theoretically result in a drop of TSH, since your body would then need less hormone to stimulate your thyroid less. If my T4 was low, I would expect to have a high TSH level. Since my T4 is normal, my TSH should be normal as well. My T4 has been stabilized with 100mg of levothyroxine for over two years.