Journal List > Int J Thyroidol > v.9(1) > 1082753

Int J Thyroidol. 2016 May;9(1):39-42. Korean.
Published online May 31, 2016.
Copyright © 2016. the Korean Thyroid Association. All rights reserved.
Hyponatremia after Radioactive Iodine Treatment in Thyroid Cancer Patients
Oh Chan Kwon, Hoon Hee Lee, Kyung Hwan Oh and Tae Yong Kim
Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.

Correspondence: Tae Yong Kim, MD, PhD, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505, Korea. Tel: 82-2-3010-6962, Fax: 82-2-3010-3249, Email:
Received December 16, 2015; Revised February 23, 2016; Accepted March 07, 2016.

This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.


Radioactive iodine treatment (RAIT) after surgery reduces local recurrence and cancer related death. Cases of hyponatremia after preparation for RAIT have rarely been reported. We report 4 cases of hyponatremia which developed after RAIT. The cause of hyponatremia seemed to be related with over ingestion of free water which is recommended during RAIT. These cases highlighted the importance of weight adjusted water ingestion during RAIT.

Keywords: Thyroid neoplasms; Iodine radioisotopes; Hyponatremia; Water intoxication


Table 1
Patient characteristics
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