Do you add liothyronine or switch to combination therapy in an athyreotic patient on levothyroxine with persistent hypothyroid-like symptoms, a normal TSH, and a low FT3, given emerging data suggesting reduced peripheral thyroid hormone action in this subgroup?

The standard treatment for hypothyroidism remains substitution with T4 alone.

Even when the TSH level is brought to the desired therapeutic range, some patients continue to complain of hypothyroid-like symptoms.

In order to correct that, a combination of T4 and T3 has been tried.

However, whether a com...

I would not add liothyronine to levothyroxine therapy for thyroid hormone replacement in a hypothyroid patient based on this study. The study has an incorrect premise that the T3 in the blood is the "important" T3. Actually, T4 is converted intracellularly to T3, and then within the cell T3 regulate...