A Case of Severe Overt Hypothyroidism Induced by Long-Term Habitual Gargling with Povidone-Iodine for Over 40 Years
Abstract
We herein present a case of severe overt hypothyroidism that developed following habitual gargling with povidone-iodine twice daily for >40 years. The patient showed elevated urinary iodine excretion and negative thyroid autoantibodies (thyroglobulin, thyroid peroxidase, and thyrotropin receptor antibodies). After the discontinuation of gargling, the thyroid function and urinary iodine levels normalized within approximately one month. This is the first reported case in which urinary iodine levels were measured before and after the cessation of povidone-iodine gargling. Our findings provide clinical insights into iodine-induced thyroid dysfunction arising from a widely available antiseptic, offering valuable guidance for clinicians involved in thyroid care.
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BibTeX
@article{fukata2026case,
title = {{A Case of Severe Overt Hypothyroidism Induced by Long-Term Habitual Gargling with Povidone-Iodine for Over 40 Years}},
author = {Shuji Fukata and Yoshiki Furumura and Hanna Deguchi-Horiuchi and Eijun Nishihara and Mitsuru Ito and Mitsushige Nishikawa and Akira Miyauchi and Takashi Akamizu},
journal = {Internal Medicine},
year = {2026},
month = aug,
doi = {10.2169/internalmedicine.7596-26},
url = {https://www.jstage.jst.go.jp/article/internalmedicine/advpub/0/advpub_7596-26/_article},
note = {CC BY-NC-ND},
}
RIS
TY - JOUR
TI - A Case of Severe Overt Hypothyroidism Induced by Long-Term Habitual Gargling with Povidone-Iodine for Over 40 Years
AU - Shuji Fukata
AU - Yoshiki Furumura
AU - Hanna Deguchi-Horiuchi
AU - Eijun Nishihara
AU - Mitsuru Ito
AU - Mitsushige Nishikawa
AU - Akira Miyauchi
AU - Takashi Akamizu
PY - 2026
DA - 2026/08/08
JO - Internal Medicine
DO - 10.2169/internalmedicine.7596-26
UR - https://www.jstage.jst.go.jp/article/internalmedicine/advpub/0/advpub_7596-26/_article
AB - We herein present a case of severe overt hypothyroidism that developed following habitual gargling with povidone-iodine twice daily for >40 years. The patient showed elevated urinary iodine excretion and negative thyroid autoantibodies (thyroglobulin, thyroid peroxidase, and thyrotropin receptor antibodies). After the discontinuation of gargling, the thyroid function and urinary iodine levels normalized within approximately one month. This is the first reported case in which urinary iodine levels were measured before and after the cessation of povidone-iodine gargling. Our findings provide clinical insights into iodine-induced thyroid dysfunction arising from a widely available antiseptic, offering valuable guidance for clinicians involved in thyroid care.
SN - 1349-7235
SN - 0918-2918
ER -