Combined LT3 and LT4 therapy for precision medicine: easier with TTCombo system.

Hypothyroidism is typically treated with levothyroxine monotherapy. However, despite normalized serum thyroid-stimulating hormone levels, 5-10% of patients continue to experience persistent symptoms, raising concerns about the adequacy of thyroxine monotherapy. Combination therapy with levothyroxine and liothyronine has been proposed as an alternative, but it presents practical challenges, including dosing complexity, the short half-life of triiodothyronine, increased monitoring requirements, and potential adverse effects. Moreover, there is no clear consensus within the medical community regarding the superiority of combination therapy over levothyroxine monotherapy, although some studies indicate potential benefits in specific patient populations. Genetic factors, such as polymorphisms in the DIO2 gene, may influence individual responses to therapy, further complicating treatment. To address the limitations of combination therapy, we propose a novel approach: TTCombo. This digital health technology delivers personalized doses of levothyroxine and liothyronine, improving treatment adherence and optimizing outcomes. By providing individualized, physiologically tailored hormone replacement, TTCombo has the potential to revolutionize hypothyroidism management and enhance patient quality of life.