Definition:

Thyrotoxic hypokalemic periodic paralysis (TPP) is characterized by thyrotoxicosis in combination with typical episodes of hypokalemic periodic paralysis (HypoPP). People of Asian descent are most often affected, but all ethnicities can present with TPP. Hypokalemia is typical during paralysis, but is not always detected; administration of potassium during the attacks should be offered cautiously, preferably orally, to prevent rebound hyperkalemia. Mutations have been identified in TPP patients in an inwardly rectifying potassium channel, , that is expressed in muscle and transcriptionally regulated by thyroid hormone. Mutations in Kir2.6, which occur in up to 33% of patients, reinforces the hypothesis of genetic heterogeneity in patients with TPP.