Attacks seldom occur during exercise but may be triggered by rest following exercise. Disorders that cause intermittent episodes of paralysis as their primary effect are uncommon. More commonly, an intermittent episodes of paralysis or weakness is a symptom of another disorder. Hyperkalemic periodic paralysis occurs in approximately 1 out of 100,000 people. Men are affected more often than women and usually have more severe symptoms.
Treatment prevents attacks of weakness .
Between attacks, examination is normal. During an attack, reflexes may be decreased or absent. Serum potassium is normal or high during attacks and may be normal or high between attacks. The goals of treatment are relief of acute symptoms and prevention of further attacks. Attacks are seldom severe enough to require emergency treatment.