Oral L-thyroxine liquid versus tablet in patients submitted to total thyroidectomy for thyroid cancer (without malabsorption): A prospective study

Objective: No consistent data are present in literature about the effectiveness of Levothyroxine (L-T4) liquid formulation in patients without malabsorption after thyroidectomy. The aim of this study is to compare the effectiveness of L-T4 liquid formulation, with L-T4 tablets, in thyroid cancer patients after thyroidectomy (without malabsorption or drug interference). Methods: One hundred five patients were recruited; 52 patients were treated with liquid L-T4 formulation, while 53 with L-T4 tablets, at the same dosage (1.5 mcg/kg/day). Patients started to assume the drug the day after surgery, 30 min before breakfast. In both groups circulating levels of thyrotropic hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) were dosed at week 6 (first control), and then at week 12 (second control). Results: We obtained significantly lower TSH values in the liquid L-T4 group patients, compared to the tablet L-T4 group, at the first control (P < .05), and at the second control (P < .01), while FT4 and FT3 levels were not significantly different. Hypothyroid range (TSH > 3.6 mcU/mL) was significantly more prevalent in the patients treated with L-T4 tablet. Conclusions: A better control of TSH was observed in thyroidectomized patients (without malabsorption, gastric disorders, or drug interference) with liquid L-T4 regimen. Level of Evidence: 2c-Outcomes Research.