The whole trick is to start with a steady level of T3 and keep it steady (see Q13).

If this is not the first cycle, then sufficient time should be allowed between cycles to allow the T3 levels to steady down (p96). If this is the first cycle, then the T3 level should be endogenously steady (p88). Or the patient may be taking a T4-containing medicine, which should be weaned prior to initiation of T3 therapy.