MON-564 Patients Thyroidectomized For Thyroid Cancer (without Malabsorption) In Treatment With L-thyroxine (L-T4) In Soft Gel Capsule Formulation

Since the effectiveness of levothyroxine (L-T4) in soft gel capsule formulation in patients recently subjected to total thyroidectomy is not yet well known, we investigated on its efficacy in comparison to L-T4 tablets in these type of patients, who not reported any issues of malabsorption or drug interference. In our study we have included 230 patients who were split in two groups: one of 115 in treatment with soft gel capsule L-T4 formulation, the other one of 115 in treatment with L-T4 tablets. All subjects received the same dosage of L-T4 (1.5 mcg/kg/day), administered 30 min before breakfast. The treatment started the day after surgery, then at week 6 (1st control), and at week 12 (2nd control) for both the groups of patients, thyrotropic hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) were evaluated. We observed significantly lower TSH values in the soft gel capsule L-T4 group, in comparison to the tablet L-T4 group, in both the first (P < 0.05) and the second control (P < 0.01), meanwhile no significant differences were observed for FT4 and FT3 levels. In the L-T4 tablet group a higher prevalence of patients in the hypothyroid range (TSH>3.6 mcU/ml) was present with respect to that observed in the soft gel capsule L-T4 group. In conclusion, a better control of TSH levels in patients previously undergone to total thyroidectomy for thyroid cancer (not reporting issues of malabsorption, gastric disorders, or drug interference) has been obtained with soft gel capsule L-T4 respect to L-T4 tablets.