A young man presenting with paralysis after vigorous exercise.

Thyrotoxic periodic paralysis (TPP) is a rare metabolic disorder characterised by muscular weakness and paralysis in predisposed thyrotoxic patients. Although patients with TPP are almost uniformly men of Asian descent, cases have been reported in Caucasian and other ethnic populations. The rapid increase in ethnic diversity in Western and European nations has led to increase in TPP reports, where it was once considered exceedingly rare.