Exp Clin Endocrinol Diabetes 2006; 114(5): 222-226
DOI: 10.1055/s-2006-924238

J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart · New York

Influence of Short-Term Interruption of Antithyroid Drugs on the Outcome of Radioiodine Therapy of Graves' Disease: Results of a Prospective Study

S. M. Eschmann1 , M. H. Thelen1 , H. Dittmann1 , R. Bares1
  • 1University of Tuebingen, Department of Nuclear Medicine, Tuebingen, Germany
Further Information

Publication History

Received: August 22, 2005 First decision: October 14, 2005

Accepted: March 27, 2006

Publication Date:
28 June 2006 (online)


Aim: The factors influencing success of treating Graves' disease with radioiodine (131I) are discussed controversially. This study analyses prospectively the influence of discontinuing antithyroid drugs (ATD) immediately prior to treatment with radioiodine on the therapeutic outcome. Methods: We studied 141 patients with Graves' disease. In 73 of them (group A) treatment was performed under medication with ATD, in 68 patients (group B) ATD were discontinued for 3 - 7 days starting at the time of therapy. We performed a statistical analysis of the influence of ATD and other factors potentially influencing treatment results. Results: In group A 49/73 patients were treated successfully (67 %) vs. 58/68 (85 %) in group B (p < 0.01). Characteristic changes in the kinetics of radioiodine were observed: after discontinuing ATD specific uptake was higher (2.0 %/ml in group A vs. 2.6 %/ml in group B, p = 0.004), and the effective half life was longer (5.1 ± 1.3 d in group A vs. 5.5 ± 1.1 d in group B, p = 0.076) resulting in a significantly higher radiation dose in group B (200 ± 61 Gy in group A vs. 236 ± 72 Gy in group B, p = 0.002). Conclusion: We conclude that short-term interruption of ATD improves the success rate of treating Graves' disease with radioiodine significantly.


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MD Susanne-Martina Eschmann

Department of Nuclear Medicine
University of Tuebingen

Otfried-Mueller-Str. 14

72076 Tuebingen


Phone: +49/7071/2986412

Fax: +49/7071/295869

Email: susanne-martina.eschmann@med.uni-tuebingen.de