What is the Wolff-Chaikoff effect?
In cases of excess iodine, iodine uptake in the thyroid gland is blocked by a decreased activity of the iodine symporter, leading to reduced T4 and increased TSH concentrations.
Vlaardingerbroek H. Unusual cause of congenital hypothyroidism in a term infant. BMJ Case Rep. 2021 Feb 19;14(2):e237930. doi: 10.1136/bcr-2020-237930. PMID: 33608335; PMCID: PMC7896560.