In this study we enrolled 160 patients who had been recently subjected to total thyroidectomy, not reporting malabsorption or drug interference issues. Our aim was to study the efficacy of levothyroxine (L-T4) liquid formulation in comparison to L-T4 tablets, therefore 80 patients received liquid L-T4 formulation, whereas 80 took L-T4 tablets using the same dosage (1.5 mcg/kg/day). The treatment with L-T4, administered 30 min before breakfast, started the day after surgery. In both groups were assessed: thyrotropic hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3), after 6 weeks (1st control), and then after 12 weeks (2nd control). We observed significantly lower TSH levels in the liquid L-T4 group with respect to the tablet L-T4 ones, either for the first (P < 0.05) and for the second control (P < 0.01), while no significant differences arose for FT4 and FT3. Moreover the prevalence of hypothyroid patients (TSH>3.6 mcU/ml) was higher in the L-T4 tablet group with respect to the liquid L-T4 group.
These results indicate a better control of TSH levels by liquid L-T4 (vs. L-T4 tablets) in patients previously subjected to total thyroidectomy for thyroid cancer without issues of malabsorption, drug interference, or gastric disorders.