Canadian Journal of Medicine

Thyrotoxic Periodic Paralysis (TPP) is an acute potentially lethal emergency in patients with hyperthyroidism who present with sudden muscle weakness and hypokalemia. It is commonly precipitated by high carbohydrate or high salt content meals, strenuous exercise, stress, trauma, glucocorticoids, epinephrine, alcohol, or respiratory infections. COVID-19 infection or vaccination may represent a novel trigger for TPP. Furthermore, COVID-19 infection or vaccination may incite inflammatory processes leading to thyrotoxicosis, which can manifest as TPP. While COVID-19 causing subacute thyroiditis, euthyroid sick syndrome, Hashimoto’s disease, or Graves’ disease have been well documented in the literature; there have only been six case reports of post-COVID-19 TPP. Notably, all cases thus far have been restricted to male patients, and there is paucity of literature from North America. The purpose of this paper is to outline the first case of post-COVID-19 TPP in a female patient, who presented to the emergency department with acute paralysis and severe hypokalemia (2.2 mmol/L) three months after COVID-19 infection. Investigations in the emergency department showed thyrotoxicosis. She was treated with potassium replacement, which improved her paralysis. Subsequent investigations revealed severe hyperthyroidism from Graves’ disease, which is currently managed with metoprolol and methimazole. Her hyperthyroidism improved without recurrent hypokalemia or paralysis. In addition, we outline the epidemiology, pathophysiology, precipitants, and management of TPP, with a particular focus on COVID-19 infection or vaccination precipitating TPP. We discuss post-COVID-19 TPP cases thus far described in the literature. Knowing that North American COVID-19 infection waves lagged Asia, we could anticipate additional future TPP cases.