What is the Wolf-Chaikoff effect?

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From the Research

The Wolff-Chaikoff effect is a protective mechanism where the thyroid gland temporarily reduces thyroid hormone production when exposed to large amounts of iodine, and this effect typically lasts for a few days, after which most healthy thyroids "escape" from this inhibition and resume normal function, as supported by the most recent study 1. The Wolff-Chaikoff effect is characterized by the thyroid gland's ability to block the uptake and organification of iodine, preventing overproduction of thyroid hormones that could lead to hyperthyroidism.

  • This effect is usually temporary and within a few days thyroid hormone synthesis returns to normal through the so-called 'escape' phenomenon, as described in 2.
  • However, in some individuals with underlying thyroid disease or the elderly, this escape mechanism may fail, resulting in hypothyroidism, as noted in 3 and 4. The Wolff-Chaikoff effect has clinical implications, particularly when patients receive iodine-containing medications like amiodarone or iodinated contrast media for imaging studies.
  • Healthcare providers should monitor thyroid function in patients receiving high iodine loads, especially those with pre-existing thyroid conditions, as they may be more susceptible to developing thyroid dysfunction, as highlighted in 1 and 5. It is essential to consider the potential risks and consequences of iodine excess, including hypothyroidism and thyrotoxicosis, and to carefully monitor patients who are receiving high iodine loads, as emphasized in 2 and 3.
  • The use of iodinated contrast media in radiologic studies or invasive medical procedures is a common source of excessive iodine exposure and can lead to thyroid dysfunction, as reported in 1.
  • Therefore, healthcare providers should be aware of the Wolff-Chaikoff effect and its potential consequences, and take steps to monitor and manage thyroid function in patients who are at risk, as supported by the most recent and highest quality study 1.

References

Research

Iodine-Induced hypothyroidism.

Thyroid : official journal of the American Thyroid Association, 2001

Research

Iodine excess.

Best practice & research. Clinical endocrinology & metabolism, 2010

Research

[Hypothyroidism related to excess iodine].

Presse medicale (Paris, France : 1983), 2002

Research

Iodine and thyroid disease.

The Medical clinics of North America, 1991

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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