Hypokalemic periodic paralysis is a relatively rare disease in which individuals experience transient, severe episodes of hypokalemia as a result of rapid intracellular potassium shift into skeletal muscle. The attacks typically manifest as muscle cramps, muscle paralysis, or cardiac arrhythmias, and may are classically precipitated by rest following exercise, catecholamine excess, or carbohydrate-rich meals.
The acquired form in most instances is associated with thyrotoxicosis. Even though more women than men suffer from hyperthyroidism, there is a huge male predominance (up to a 70:1 M:F ratio) of hyperthyroid-induced hypokalemic periodic paralysis. The disorder seems to be especially common in Asian populations.
In contrast, the hereditary forms of hypokalemic periodic paralysis have a roughly equal M:F ratio, have a younger age of onset (