Antonelli, Alessandro1, Fallahi, Poupak1, Ferrari, Silvia Martina1, Materazzi, Gabriele2, Ragusa, Francesca1, Paparo, Sabrina Rosaria1, 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: No study in the literature has evaluated the effectiveness of levothyroxine (L-T4) soft gel capsule formulation in patients recently submitted to total thyroidectomy for thyroid cancer. The aim of this study was to compare the effectiveness of L-T4 gel capsule, with L-T4 tablets, in patients recently submitted to total thyroidectomy for thyroid cancer (without malabsorption or drug interference).
Methods: Twenty-eight patients were consecutively recruited: 14 patients were treated with L-T4 therapy in tablets, while 14 with gel capsule 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 L-T4 gel capsule group, than in L-T4 tablet 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>3.5 mcU/ml) was significantly higher in the L-T4 tablet group.
Discussion & Conclusion: These results suggest that soft L-T4 gel capsule is more effective than L-T4 tablets in controlling TSH levels in patients thyroidectomized for thyroid cancer without malabsorption, gastric disorders, or drug interference. However a larger number of studied patients is necessary to obtain a definitive result.