Presentation Number: OR50-4
Date of Presentation: June 18th, 2013

Camilla Virili1, Maria Giulia Santaguida2, Miriam Cellini3, Susanna Carlotta Del Duca3, Lucilla Gargano4 and Marco Centanni*5
1Sapienza, University of Rome, Latina, Italy, 2Sapienza, University of Rome, Rome, Italy, 3"Sapienza" Università di Roma, Latina, Italy, 4AUSL Latina, Latina, Italy, 5Sapienza, University of Rome


An intact gastric acid secretion seems to be crucial for subsequent intestinal T4 absorption. Patients with gastrointestinal disorders (e.g. H.pylori infection, lactose intolerance, celiac disease) show some resistance to thyroxine treatment. Patients with unrecognized gastric disorders, in whom larger doses of thyroxine tablets are required, often undergo dose changing and redundant hormonal blood testing. A novel pharmaceutical preparation of thyroxine, the softgel capsules, shows better in vitro dissolution profiles in less acidic pH than the usual T4 tablet. Thus, in patients with gastric disorders, softgel capsules of T4 could make easier to attain the therapeutic target. The aim of our study has been to compare softgel and tablet T4 requirement in patients with gastric diseases. Patients enrolled in the study had T4 malabsorption and were in long-lasting T4 treatment (>5 years) with the same brand of tablets. All patients had been advised and agreed to take oral thyroxine under fasting conditions, waiting at least one hour before eating. Patients bearing additional conditions known to interfere with thyroxine treatment (e.g. drugs, pregnancy etc.) were excluded from the study. A total of 36 patients met these criteria, but only 30 of them (28F/2M; median age=51 years; median T4 dose=2.05 mg/kg/day) completed the study. In these patients T4 treatment was switched from the usual tablets to a lower dose of the softgel T4 capsules (median T4 dose=1.77 mg/kg/day; p=0.0082). Thyroid function and TSH were measured before (0 time) and after 3,6,12 and 18 months from the treatment switch. A slight serum TSH increase has been observed in some patients after 3 months of treatment, with no change in FT4 levels. After 6 months, however, despite the reduced dose of T4, mean TSH values were similar (1.82 vs 1.86 mU/l) in about 2/3 of patients (responders n=21) and so remained until the end of the study. In all the remaining patients (non responders n=9), TSH levels were significantly higher than baseline values throughout the study. In 4 of them we have detected additional intestinal disorders. Mean levels of FT4 and FT3 were in the normal range and not significantly modified throughout the study (p=ns). Lower dose of softgel T4 are thus required to reach the therapeutic goal in a significant number of patients with impaired gastric acid secretion, as compared with T4 tablet preparation.


Disclosure: MC: Clinical Researcher, IBSA, CH. Nothing to Disclose: CV, MGS, MC, SCD, LG