Lifestyle and dietary measures in Periodic Paralyses.

Periodic paralyses (PPs) are rare skeletal muscle ion channelopathies caused by mutations in skeletal muscle sodium, calcium, and potassium channel genes. PPs can be divided into primary periodic paralyses (PPPs) and secondary PPs by the aetiology. Secondary PPs are common in hyperthyroidism, primary aldosteronism, renal tubular acidosis, or be related to other causes such as medication intake or potassium loss from the digestive or renal systems. Both conditions are characterized by episodic flaccid muscle weakness. Primary PPs are classified as Hypokalemic Periodic Paralyse, (HypoPP), normokalemic periodic paralysis (NormoPP), Hyperkalemic Periodic Paralyses (HyperPP), and Andersen-Tawil Syndrome (ATS). Common features are autosomal dominant inheritance, typical onset in the first or second decades, and episodic attacks of flaccid weakness often triggered by diet or rest after exercise. The article focuses on the key role of potassium in promoting and/or preventing paralytic attacks and in avoiding them through appropriate dietary measures.