Plummer effect

In 1923 the American physician Henry Stanley Plummer discovered that high-dose iodine may be effective in the treatment of Graves’ disease.{{cite journal |last1=Plummer |first1=HS |title=Results of administering iodin to patients having exophthalmic goiter |journal=JAMA: The Journal of the American Medical Association |date=30 June 1923 |volume=80 |issue=26 |pages=1955 |doi=10.1001/jama.1923.02640530065026}}{{cite journal |last1=Loriaux |first1=D. Lynn |title=A Biographical History of Endocrinology |date=March 2016 |doi=10.1002/9781119205791.ch58}} Today, “Plummering”, i.e. therapy with Lugol's iodine solution, is one of several emergency measures in the management of severe thyrotoxicosis.{{cite book |last1=Reyes-Castano |first1=John J. |last2=Burman |first2=Kenneth |chapter=Thyrotoxic Crisis: Thyroid Storm |title=Endocrine Emergencies |date=2014 |pages=77–97 |doi=10.1007/978-1-62703-697-9_9|isbn=978-1-62703-696-2 |s2cid=68500177 }}

Via the Plummer effect, a high iodine concentration inhibits the proteolysis of thyroglobulin and the release of pre-formed thyroid hormones from thyroid follicles.{{cite journal |last1=Saller |first1=B |last2=Fink |first2=H |last3=Mann |first3=K |title=Kinetics of acute and chronic iodine excess. |journal=Experimental and Clinical Endocrinology & Diabetes |date=1998 |volume=106 Suppl 3 |pages=S34-8 |doi=10.1055/s-0029-1212044 |pmid=9865552}} Therefore, its mechanism differs from that of the Wolff–Chaikoff effect, where iodine inhibits the uptake of iodine in thyroid cells and the formation of thyroid hormones, and of the dehalogenase inhibition effect, where high iodine levels block deiodinases and other dehalogenases.{{cite journal |last1=Solis-S |first1=JC |last2=Villalobos |first2=P |last3=Orozco |first3=A |last4=Delgado |first4=G |last5=Quintanar-Stephano |first5=A |last6=Garcia-Solis |first6=P |last7=Hernandez-Montiel |first7=HL |last8=Robles-Osorio |first8=L |last9=Valverde-R |first9=C |title=Inhibition of intrathyroidal dehalogenation by iodide. |journal=The Journal of Endocrinology |date=January 2011 |volume=208 |issue=1 |pages=89–96 |doi=10.1677/JOE-10-0300 |pmid=20974636|doi-access=free }}{{cite journal |last1=Hansson |first1=M |last2=Filipsson Nyström |first2=H |last3=Jansson |first3=S |last4=Lausmaa |first4=J |last5=Berg |first5=G |title=Iodine Content and Distribution in Thyroid Specimens from Two Patients with Graves' Disease Pretreated with Either Propylthiouracil or Stable Iodine: Analysis Using X-Ray Fluorescence and Time-of-Flight Secondary Ion Mass Spectrometry. |journal=Case Reports in Endocrinology |date=2012 |volume=2012 |pages=842357 |doi=10.1155/2012/842357 |pmid=22953073|pmc=3420651 |doi-access=free }}

The Plummer effect lasts about 7 to 10 days, but unlike the Wolff-Chaikoff effect, it isn't subject to an escape phenomenon.{{cite book |last1=Nyström |first1=Ernst |last2=Berg |first2=Gertrud E. B. |last3=Jansson |first3=Svante K. G. |last4=Törring |first4=Ove |last5=Valdemarsson |first5=Stig V. |title=Thyroid disease in adults |date=2011 |publisher=Springer |location=Berlin |isbn=9783642132629 |pages=16}}

The three different mechanisms of high iodine response, the Plummer effect, the Wolff-Chaikoff inhibition effect, and the adaptive escape phenomenon, synergistically work together to fend off potentially harmful consequences of excess iodine load and ensure thyroid homeostasis.

Unlike the Wolff–Chaikoff effect, the Plummer effect does not prevent the thyroid from taking up radioactive iodine, e.g. in the case of nuclear emergencies. Therefore, "plummering" with high-dose iodine is only effective in a short time window after the release of radionuclides.{{cite journal |last1=Zanzonico |first1=PB |last2=Becker |first2=DV |title=Effects of time of administration and dietary iodine levels on potassium iodide (KI) blockade of thyroid irradiation by 131I from radioactive fallout. |journal=Health Physics |date=June 2000 |volume=78 |issue=6 |pages=660–7 |doi=10.1097/00004032-200006000-00008 |pmid=10832925|s2cid=30989865 }} Wrong timing of iodine use may even increase the risk by triggering the Plummer effect.{{cite journal |last1=Meristoudis |first1=G |last2=Ilias |first2=I |title=Caveats in the use of potassium iodide for thyroid blocking. |journal=European Journal of Nuclear Medicine and Molecular Imaging |date=June 2022 |volume=49 |issue=7 |pages=2120–2121 |doi=10.1007/s00259-022-05797-7 |pmid=35403862|s2cid=248071284 }}

The Plummer effect is, however, helpful in the management of thyrotoxicosis, where the usage of Lugol’s solution helps to limit the release of thyroid hormones into the bloodstream.

• Jod-Basedow phenomenon
• Potassium iodide
• Lugol's iodine
• Wolff–Chaikoff effect

{{Endocrinology}}

{{DEFAULTSORT:Plummer effect}}

Category:Iodine

Category:Thyroid