Thyrotoxic Hypokalemic Periodic Paralysis: A Success Story of a Diagnostic Challenge

Thyrotoxic hypokalemic periodic paralysis (THPP) is a rare but life-threatening complication of hyperthyroidism seen predominantly in males. It is generally characterized by hypokalemia and skeletal muscle paralysis requiring intensive care admission. Hypokalemia occurs due to the massive intracellular shift of potassium because of the hyperactivity of the sodium-potassium adenosine triphosphates pump (Na⁺ K⁺ ATPase). Its differential diagnosis from the other common causes of hypokalemic paralysis is essential to provide targeted therapy. We present a rare case of THPP in a female patient with no prior history of thyroid disease. THPP in this patient was precipitated by trauma and emotional stress, which served as a diagnostic challenge. Both hypokalemia and elevated levels of T3 and T4 are important diagnostic features during the acute episode. Treatment of THPP includes nonselective beta-blockade, which prevents the shift of intracellular potassium, and potassium replacement. THPP is curable once a euthyroid state is achieved.