Introduction: Effects of selected drugs on the efficacy of (131I) radioiodine therapy were examined.
Material and methods: The study involved 200 hyperthyroid patients, treated with radioactive iodine. They were divided into five (5) groups (40 persons in each). In group I beside 131I, patients were additionally administered antithyroid drugs, in group II 131I and lithium carbonate, group III 131I only (the assumed absorbed dose 150200 Gy, the same as in groups I and II, controls), in group IV 131I and corticosteroids and in group V 131I only (250350 Gy, the same as in group IV, controls). Therapeutic results were evaluated after 6 months on the basis of clinical and hormonal status. The evaluation included also effects of the initial hormonal status on the outcome of 131I therapy in groups II and IV (versus respective controls, groups III and V); such an analysis was not performed in group I because all the patients in that group were initially hyperthyroid. The results of treatment were assigned into 2 classes in each of the study groups: effective therapy euthyroidism or hypothyroidism; ineffective therapy persistent hyperthyroidism.
Results: In 145 patients (72.5%), the therapy with 131I was effective (group I 55.0%, group II 72.5%, group III 75.5%, group IV 87.5%, group V 70.0%). In 55 patients (27.5%), the therapy with 131I turned out ineffective.
Conclusions: The application of thiamazole during peritherapeutic period in patients, treated with 131I, reduced the effectiveness of radioiodine, while lithium carbonate had no effect on the therapy outcome. Prednisone increased the effectiveness of the therapy with radioiodine. Normalisation of the initial concentration of TSH was favourable for the 131I therapeutic outcome only when the assumed absorbed doses of 150200 Gy were applied.
25 - 29 Apr 2009
European Society of Endocrinology