This depends on where one is in the therapy, and why the cycle was being weaned. If a cycle was being weaned because of side effects: If the side effects resolve while the patient is weaning down off the medicine, then one can stay off the treatment for 2 – 3 days before starting back up again. But what if the side effects only begin to resolve while the patient is weaning down off the T3 therapy, and resolve completely only after the patient is off the therapy for a couple of days? In that case I’d recommend the patient staying off the T3 therapy for another couple of days after that to allow the T3 to steady down further to provide a steadier T3 foundation and better start for the next cycle.
Theoretically, if someone wanted to let the T3 level steady down as much as possible, one could argue that the patient should remain off the T3 for about two weeks. Even so, most of the steadying is probably accomplished within about 10 days, so there is probably not much added benefit in staying off the T3 for much longer than that. This approach is indicated when one would like to eliminate the unsteadiness as much as possible to see if the patient will respond well to treatment. It also underscores the importance of not taking a steady start for granted, since if the T3 levels are destabilized (muddying the water, so to speak) right from the start, it would take quite a bit of time to reproduce another opportunity with that patient at so steady a start.