Antonelli, Alessandro1; Fallahi, Poupak1, Ferrari, Silvia Martina1, Materazzi, Gabriele2, Ragusa, Francesca1, Ruffilli, Ilaria1, Patrizio, Armando1, Miccoli, Paolo2,
1 Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
2 Department of Surgical, Medical, Molecular Pathology and Critical Area, University of Pisa, Pisa, Italy
Background. Few studies have evaluated the effectiveness of levothyroxine (L-T4) liquid formulation in patients recently submitted to total thyroidectomy. The aim of this study was to compare the effectiveness of L-T4 liquid formulation with L-T4 tablets, in patients recently submitted to total thyroidectomy for thyroid cancer (without malabsorption or drug interference).
Methods. Thirty-four patients were consecutively recruited: 17 patients were treated with L-T4 therapy in tablets, while 17 with liquid L-T4 at the same dosage (1.5 mcg/kg/day), 30 min before breakfast, starting the day after thyroidectomy. Serum thyrotropic hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) were re-evaluated after 6 weeks (first control) and 12 weeks (second control) in both groups.
Results. TSH values were significantly lower in the liquid L-T4 group, than in the tablet L-T4 group, both at the first control (P < 0.05) and at the second control (P < 0.01); FT4 and FT3 levels were not significantly different. The prevalence of patients in the hypothyroid range (TSH>3.6 mcU/ml) was significantly higher in the L-T4 tablet group.
Discussion & Conclusion. These results suggest that liquid L-T4 is more effective than L-T4 in tablets in controlling TSH levels in thyroidectomized patients for thyroid cancer without malabsorption, gastric disorders, or drug interference.